solar energy field trip
DESCRIPTION
Take a Field Trip with Science Companion!Join us for a virtual field trip to the largest solar power plant in the US with a very special guest, and then explore our lesson on energy transfers and solar energy from our inquiry-based science curriculum module, Energy.Let us know what you think!TRANSCRIPT
Solar Energy
Science Companion Field TripsA “Science in Real Life” Series
Science Field Trip
A Visit to a Solar Power Plant with a Special Guest
A Lesson on Energy Transfers
from the Energy Module
Student Reference Book Pages
Come on a virtual field trip matching module sample lessons with current events!
www.sciencecompanion.com
Solar Energy in Florida!
A special guest was invited for the opening, to celebrate how solar energy can change America...
Can you see all of the solar panels behind the podium?
On October 29, 2009, the world’s largest solar power installation was opened at Florida Power and Light, a utility company in Sarasota, Florida.
90,000 solar panels!
Not this guy!(But he came with the special guest...)
We’ll give you a hint!
Rita, Science Companion’s director, was there to greet him, waiting in front of this sign...
“It’s an honor to be here on a very big day not just for Arcadia but for the cause of clean energy in America,” President Obama told the crowd...
“With the flip of a switch, Florida Power and Light has moved the solar panels behind me into a position where they can catch the sun’s rays. And now, for the very first time, a large-scale solar power plant...will deliver electricity produced by the sun to the citizens of the Sunshine State.”
Solar power works through the transfer of energy -- turn the page and find out how!
http://www.sun-sentinel.com/business/sfl-obama-fpl-102809,0,81543.story
Levels 4-6
Science Companion®
Energy
Teacher Lesson Manual
DevelopersBelinda Basca, Diane Bell, and Martha Sullivan
EditorsRachel Burke and Wanda Gayle
Technical Art and GraphicsColin Hayes, Anthony Lewis, and Bill Reiswig
Book ProductionHappenstance Type-O-Rama; Picas & Points, Plus (Carolyn Loxton)
Pedagogy and Content AdvisorsJean Bell, Max Bell, Cindy Buchenroth-Martin, Nick Cabot*, Debbie Clement*, Josie Grotenhuis*, Catherine Grubin, Tim Strains*, and Robert Ward
* Indicates a scientist or science educator who contributed advice or expertise, but who is not part of the Chicago Science Group. Ultimately, responsibility for what is included or omitted from our material rests with the Chicago Science Group.
Field Test TeachersJoyce Berry, Suze Bodwell, Jim Elwell, Nancy Florig, David Grelecki, Matt Laughlin, Lisette Mirabile, Valerie Powell, Jen Ryan, Chris Sanborn, Kitty Skow, Jane Stephenson, Will Whitlock, and Nancy Zordan
www.sciencecompanion.com
2009 Edition
Copyright © 2005 Chicago Science Group.
All Rights Reserved
Printed in the United States of America. Except as permitted under the United States Copyright Act, no part of this publication may be reproduced or distributed in any form or by any means or stored in a database or retrieval system without the prior written permission of the publisher.
SCIENCE COMPANION®, EXPLORAGEAR®, the CROSSHATCH Design™ and the WHEEL Design® are trademarks of Chicago Science Group and Chicago Educational Publishing.
ISBN 1-59192-284-4
1 2 3 4 5 6 7 8 9 10-P001-17 16 15 14 13 12 11 10 09 08
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Skill Building ActivitiesReading Science Books . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Measuring Temperature Accurately . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Making Line Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Designing a Fair Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Teacher Background Information . . . . . . . . . . . . . . . . . . . 234
Standards and BenchmarksStandards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Benchmarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
Teacher Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
Table of ContentsSuggested Full Year Schedule . . . . . . . . . .Inside Front Cover
Welcome to Science CompanionPhilosophy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Finding What You Need in Science Companion . . . . . . . . . . . . . . . . . . 8
Cross-Curricular Integration and Flexible Scheduling . . . . . . . . . . . 10
Differentiating Instruction for Diverse Learners . . . . . . . . . . . . . . . . . 12
Unit OverviewIntroduction to the Energy Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Unit Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Lessons at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Integrating the Student Reference Book . . . . . . . . . . . . . . . . . . . . . . . . 32
Preparing for the UnitEnergy Science Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Science Library and Web Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Before You Begin Teaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Lessons1 Energy Is All Around Us* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
2 Energy’s Many Forms* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
3 Energy Transfers: How Energy Makes Things Happen* . . . . . . 80
Teacher Directions: Setting Up the Energy Stations . . . . . . . . . 95
4 Energy Transfers: Making Boats Go . . . . . . . . . . . . . . . . . . . . . . . . 100
Teacher Directions: Making a Solar Pulley . . . . . . . . . . . . . . . . . . 112
5 Hot Water, Cold Water: Transferring Heat Energy* . . . . . . . . . . 116
6 Conductors: Testing the Transfer of Heat Energy* . . . . . . . . . . 132
7 Building a Better Water Bottle: . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Slowing the Transfer of Heat Energy*
8 Getting More for Less: Energy Efficiency . . . . . . . . . . . . . . . . . . . 164
9 Inventions: Getting Energy to Work for Us* . . . . . . . . . . . . . . . . 180
* Indicates a core lesson
| ENERGY | TablE of CoNTENTs
�
Skill Building ActivitiesReading Science Books . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Measuring Temperature Accurately . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Making Line Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Designing a Fair Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Teacher Background Information . . . . . . . . . . . . . . . . . . . 234
Standards and BenchmarksStandards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Benchmarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
Teacher Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
Table of ContentsSuggested Full Year Schedule . . . . . . . . . .Inside Front Cover
Welcome to Science CompanionPhilosophy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Finding What You Need in Science Companion . . . . . . . . . . . . . . . . . . 8
Cross-Curricular Integration and Flexible Scheduling . . . . . . . . . . . 10
Differentiating Instruction for Diverse Learners . . . . . . . . . . . . . . . . . 12
Unit OverviewIntroduction to the Energy Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Unit Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Lessons at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Integrating the Student Reference Book . . . . . . . . . . . . . . . . . . . . . . . . 32
Preparing for the UnitEnergy Science Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Science Library and Web Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Before You Begin Teaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Lessons1 Energy Is All Around Us* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
2 Energy’s Many Forms* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
3 Energy Transfers: How Energy Makes Things Happen* . . . . . . 80
Teacher Directions: Setting Up the Energy Stations . . . . . . . . . 95
4 Energy Transfers: Making Boats Go . . . . . . . . . . . . . . . . . . . . . . . . 100
Teacher Directions: Making a Solar Pulley . . . . . . . . . . . . . . . . . . 113
5 Hot Water, Cold Water: Transferring Heat Energy* . . . . . . . . . . 116
6 Conductors: Testing the Transfer of Heat Energy* . . . . . . . . . . 132
7 Building a Better Water Bottle: . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Slowing the Transfer of Heat Energy*
8 Getting More for Less: Energy Efficiency . . . . . . . . . . . . . . . . . . . 164
9 Inventions: Getting Energy to Work for Us* . . . . . . . . . . . . . . . . 180
* Indicates a core lesson
ENERGY | TablE of CoNTENTs |
6
PhilosophyAlmost anyone who has spent time with children is struck by the tremendous energy they expend exploring their world. They ask “why” and “how.” They want to see and touch. They use their minds and senses to explore the things they encounter and wonder about. In other words, children are already equipped with the basic qualities that make a good scientist.
The goal of the Science Companion curriculum is to respond to and nourish students’ scientific dispositions by actively engaging their interests and enhancing their powers of inquiry, observation, and reflection. Learning by doing is central to this program.
Each Science Companion lesson incorporates interesting and relevant scientific content, as well as science values, attitudes, and skills that children in the elementary grades should begin to develop. These “habits of mind,” along with science content knowledge, are crucial for building science literacy and they are an integral part of the Science Companion program. Be aware of them and reinforce them as you work with students. With experience, students will develop the ways they demonstrate and use the following scientific habits of mind.
Habits of MindWondering and thinking about the natural and physical worldStudents’ curiosity is valued, respected, and nurtured. Their questions and theories about the world around them are important in setting direction and pace for the curriculum. Children are encouraged to revise and refine their questions and ideas as they gain additional information through a variety of sources and experiences.
Seeking answers through exploration and investigationStudents actively seek information and answers to their questions by trying things out and making observations. They continually revise their understanding based on their experiences. Through these investigations, children learn firsthand about the “scientific method.” They also see that taking risks and making mistakes are an important part of science and of learning in general.
Pursuing ideas in depthStudents have the opportunity to pursue ideas and topics fully, revisiting them and making connections to other subjects and other areas in their lives.
Observing carefullyStudents are encouraged to attend to details. They are taught to observe with multiple senses and from a variety of perspectives. They use tools, such as magnifying lenses, balance scales, rulers, and clocks, to enhance their observations. Students use their developing mathematics and literacy skills to describe, communicate, and record their observations in age-appropriate ways.
Communicating clearlyStudents are asked to describe their observations and articulate their thinking and ideas using a variety of communication tools, including speaking, writing, and drawing. They learn that record keeping is a valuable form of communication for oneself and others. Children experience how working carefully improves one’s ability to use one’s work as a tool for communication.
Collaborating and sharingStudents come to know that their ideas, questions, observations, and work have value. At the same time, they learn that listening is vitally important, and that exchanging ideas with one another builds knowledge and enhances understanding. Children discover that they can gain more knowledge as a group than as individuals, and that detailed observations and good ideas emerge from collaboration.
Developing critical response skillsStudents ask, “How do you know?” when appropriate, and are encouraged to attempt to answer when this question is asked of them. This habit helps develop the critical response skills needed by every scientist.
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| ENERGY | PhilosoPhY
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PhilosophyAlmost anyone who has spent time with children is struck by the tremendous energy they expend exploring their world. They ask “why” and “how.” They want to see and touch. They use their minds and senses to explore the things they encounter and wonder about. In other words, children are already equipped with the basic qualities that make a good scientist.
The goal of the Science Companion curriculum is to respond to and nourish students’ scientific dispositions by actively engaging their interests and enhancing their powers of inquiry, observation, and reflection. Learning by doing is central to this program.
Each Science Companion lesson incorporates interesting and relevant scientific content, as well as science values, attitudes, and skills that children in the elementary grades should begin to develop. These “habits of mind,” along with science content knowledge, are crucial for building science literacy and they are an integral part of the Science Companion program. Be aware of them and reinforce them as you work with students. With experience, students will develop the ways they demonstrate and use the following scientific habits of mind.
Habits of MindWondering and thinking about the natural and physical worldStudents’ curiosity is valued, respected, and nurtured. Their questions and theories about the world around them are important in setting direction and pace for the curriculum. Children are encouraged to revise and refine their questions and ideas as they gain additional information through a variety of sources and experiences.
Seeking answers through exploration and investigationStudents actively seek information and answers to their questions by trying things out and making observations. They continually revise their understanding based on their experiences. Through these investigations, children learn firsthand about the “scientific method.” They also see that taking risks and making mistakes are an important part of science and of learning in general.
Pursuing ideas in depthStudents have the opportunity to pursue ideas and topics fully, revisiting them and making connections to other subjects and other areas in their lives.
Observing carefullyStudents are encouraged to attend to details. They are taught to observe with multiple senses and from a variety of perspectives. They use tools, such as magnifying lenses, balance scales, rulers, and clocks, to enhance their observations. Students use their developing mathematics and literacy skills to describe, communicate, and record their observations in age-appropriate ways.
Communicating clearlyStudents are asked to describe their observations and articulate their thinking and ideas using a variety of communication tools, including speaking, writing, and drawing. They learn that record keeping is a valuable form of communication for oneself and others. Children experience how working carefully improves one’s ability to use one’s work as a tool for communication.
Collaborating and sharingStudents come to know that their ideas, questions, observations, and work have value. At the same time, they learn that listening is vitally important, and that exchanging ideas with one another builds knowledge and enhances understanding. Children discover that they can gain more knowledge as a group than as individuals, and that detailed observations and good ideas emerge from collaboration.
Developing critical response skillsStudents ask, “How do you know?” when appropriate, and are encouraged to attempt to answer when this question is asked of them. This habit helps develop the critical response skills needed by every scientist.
WE
LCO
ME
TO
S
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ENERGY | PhilosoPhY |
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Lesson Energy Transfers: How Energy Makes Things Happen
A QUICK LOOK
Big Idea
Energy can move, or transfer, from place to place. Sometimes it changes form as it transfers.
OverviewStudents operate a variety of toys to figure out the type of energy transfers that occur in each one. They work in small groups, rotating through a series of “energy stations.”
Process Skills Key notes• Reasoning
• Explaining
• Communicating
• Schedule three sessions for this lesson.
• For the exploration, set up nine stations with enough space for small groups of students to gather around and operate each toy. See the Teacher Directions “Setting up the Energy Stations” on pages 95–98 for details.
• A solar-powered propeller and solar-activated colored beads are used in this lesson. If sunlight is not readily available in your classroom, use the compact florescent light bulb and clamp lamp provided in the ExploraGear to activate these items instead.
• For more information about the science content in this lesson, see the “Transfer of Energy” section of the Teacher Background Information on page 242.
E n E R G Y
C L U S T E R 2EnErgy transfErs
32
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Standards and BenchmarksAs they move through the energy stations, students deepen their understanding of Atlas of Scientific Literacy Benchmark 4E/E4: “Many events involve transfer of energy from one object to another,” and Atlas of Scientific Literacy Benchmark 4E/M2: “Most processes involve the transfer of energy from one system to another. Energy can be transferred in different ways.”
When the children identify the various energy forms being transferred as the toys are operated, they also expand their awareness of Physical Science Standard B (Transfer of Energy): “Energy is a property of many substances and is associated with heat, light, electricity, mechanical motion, sound, nuclei, and the nature of a chemical,” and Atlas of Scientific Literacy Benchmark 4E/M4: “Energy appears in different forms. Motion energy is associated with the speed of an object. Heat energy is associated with the temperature of an object. Gravitational energy is associated with the height of an object above a reference point. Elastic energy is associated with the stretching of an elastic object. Chemical energy is associated with the chemical composition of a substance.”
Lesson GoalRecognize that energy moves from place to place and changes forms to make things happen.
Assessment Options• Prior to the lesson, have students use their science notebook
journal section to respond to this question: Can energy move from one object to another? If so, give some examples.
• After the lesson, have students revisit the writing assignment to demonstrate how their understanding of energy transfers has grown. Consider using criterion B on Assessment 1 to note students’ progress.
• Review the Family Link Homework “Toy Box Science” to see whether students were able to independently trace the flow of energy in one of their own toys. Use criterion B on Assessment 1 to document their understanding at this time.
Energy Transfers: How Energy Makes Things Happen
A QUICK LOOK
Big Idea
Energy can move, or transfer, from place to place. Sometimes it changes form as it transfers.
OverviewStudents operate a variety of toys to figure out the type of energy transfers that occur in each one. They work in small groups, rotating through a series of “energy stations.”
Process Skills Key notes• Reasoning
• Explaining
• Communicating
• Schedule three sessions for this lesson.
• For the exploration, set up nine stations with enough space for small groups of students to gather around and operate each toy. See the Teacher Directions “Setting up the Energy Stations” on pages 95–98 for details.
• A solar-powered propeller and solar-activated colored beads are used in this lesson. If sunlight is not readily available in your classroom, use the compact florescent light bulb and clamp lamp provided in the ExploraGear to activate these items instead.
• For more information about the science content in this lesson, see the “Transfer of Energy” section of the Teacher Background Information on page 242.
Teacher Master 3, Assessment 1
Lesson 32
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PreparationSchedule three sessions for this lesson. Conduct the introductory demonstration in Session 1, rotate groups through the nine energy stations in Session 2, and follow up with the reflective discussion in Session 3.
Session 1q Locate the ExploraGear solar kit and make the solar-powered
propeller:
a. Attach the propeller to the shaft projecting from the motor.
b. Connect the wires of the solar panel to the wires of the motor.
q Prop the motor and propeller up on a small box or block as shown so that the propeller can spin freely without obstruction.
q Since light energy activates the solar propeller, position the solar panel towards a source of light energy. If enough sunlight is not available in your classroom, use the compact florescent light bulb and clamp lamp provided in the ExploraGear instead. Allow several minutes for the light bulb to warm up before doing the demonstration.
Materials
Item Quantity notesExploraGear
Clamp lamp (optional) 1 Use with a compact fluorescent light bulb to activate the solar propeller if sunlight is not available. Also used for magic bracelet beads.
Compact fluorescent light bulb (CFL), 26W 1 Use with clamp lamp to energize the solar propeller.
Solar kit To make solar propeller.
Classroom Supplies
Box or block, small 1 To prop up solar propeller.
Energy stations 9 For Session 2 exploration.
Hair dryer (optional) 1 To demonstrate that the solar panel is not activated by heat.
Overhead marker 1 To map energy transfers on an overhead transparency.
Overhead projector 1 To show overhead transparency.
Curriculum Items
Overhead Transparency “Mapping Energy Transfers”
Energy Science Notebook, pages 4–13
Energy Student Reference Book, pages 13–24 and 129-146
Teacher Directions “Setting up the Energy Stations”
Teacher Master “Energy Station Directions”
Energy Assessment 1 “Energy Forms and Transfers” (optional)
Family Link Homework “Toy Box Science”
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�3
PreparationSchedule three sessions for this lesson. Conduct the introductory demonstration in Session 1, rotate groups through the nine energy stations in Session 2, and follow up with the reflective discussion in Session 3.
Session 1q Locate the ExploraGear solar kit and make the solar-powered
propeller:
a. Attach the propeller to the shaft projecting from the motor.
b. Connect the wires of the solar panel to the wires of the motor.
q Prop the motor and propeller up on a small box or block as shown so that the propeller can spin freely without obstruction.
q Since light energy activates the solar propeller, position the solar panel towards a source of light energy. If enough sunlight is not available in your classroom, use the compact florescent light bulb and clamp lamp provided in the ExploraGear instead. Allow several minutes for the light bulb to warm up before doing the demonstration.
Materials
Item Quantity notesExploraGear
Clamp lamp (optional) 1 Use with a compact fluorescent light bulb to activate the solar propeller if sunlight is not available. Also used for magic bracelet beads.
Compact fluorescent light bulb (CFL), 26W 1 Use with clamp lamp to energize the solar propeller.
Solar kit To make solar propeller.
Classroom Supplies
Box or block, small 1 To prop up solar propeller.
Energy stations 9 For Session 2 exploration.
Hair dryer (optional) 1 To demonstrate that the solar panel is not activated by heat.
Overhead marker 1 To map energy transfers on an overhead transparency.
Overhead projector 1 To show overhead transparency.
Curriculum Items
Overhead Transparency “Mapping Energy Transfers”
Energy Science Notebook, pages 4–13
Energy Student Reference Book, pages 13–24 and 129-146
Teacher Directions “Setting up the Energy Stations”
Teacher Master “Energy Station Directions”
Energy Assessment 1 “Energy Forms and Transfers” (optional)
Family Link Homework “Toy Box Science”
ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN |
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Teaching the LessonSESSIOn 1
Engage
Sensory Observation
Have the students reflect on the “I Wonder” circle as they observe the solar propeller responding to sunlight. Help them see how observations (the propeller spins when sunlight hits the panel, but stops when sunlight is absent) lead to discovery (light energy is being transferred from the sun to activate the solar panel).
1. Show the class the solar propeller. Without explaining how it works, allow students to see how sunlight striking the solar panel makes the propeller spin. Cover up the solar panel with your hand to make it stop.
Teacher NoTe: If it is a sunny day with patchy clouds, simply set the unit in a window and allow students to figure out on their own that the propeller spins rapidly when the sun shines and slows down or even stops when passing clouds block the sun.
2. Discuss where the propeller gets the energy to spin. (Students should recognize that when light shines on the panel the propeller has the energy to spin and when the light is blocked the propeller no longer has the energy to spin.)
Teacher NoTe: If some students believe that the sun’s or the lamp’s heat rather than its light powers the propeller, you can direct hot air from a hair dryer onto the solar panel to show that heat energy alone does not cause the propeller to spin.
3. Introduce the term energy transfer to describe instances where energy moves from one place or object to another (such as from the sun to the solar panel), or changes from one form to another (such as in the solar panel itself, where light energy is changed to electrical energy). Tell the class that they have three fun science sessions to look forward to—they get to explore energy transfers using toys.
Session 2q Set up the nine energy stations as described in the Teacher
Directions “Setting up the Energy Stations” on pages 95–98. Follow these steps before setting up the stations:
a. Make a copy of the Teacher Master “Energy Station Directions.” Cut along the dotted lines to create separate toy operation directions for each station.
b. Bright, direct sunlight is needed to activate the magic bracelet at Energy Station 9. They will not activate using an incandescent bulb or out of direct sunlight. If sunlight is not available, use the compact fluorescent light bulb and clamp lamp provided in the ExploraGear. Allow time for the light bulb to warm up before sending students to the station.
c. Allow ample time to run through each station after set-up to troubleshoot any problems and ensure that the toys are working properly.
q Copy the Family Link Homework “Toy Box Science” to send home with the students.
Using the Student Reference Book• After Session 1, use Chapter 2 of the student reference book to
reinforce the concept of energy transfers.
• (Optional) At the end of this lesson, refer students to the timeline “A Walk Through Energy History” on page 129–146 of the student reference book. Challenge the class to identify the energy transfers associated with several of the timeline events.
Vocabularyenergy transfer . . . . . When energy moves from one object or
place to another or changes from one form to another.
solar energy . . . . . . . . Energy transferred from the sun. Solar energy travels to Earth through space and provides warmth, light, and energy for plant growth.
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Teaching the LessonSESSIOn 1
Engage
Sensory Observation
Have the students reflect on the “I Wonder” circle as they observe the solar propeller responding to sunlight. Help them see how observations (the propeller spins when sunlight hits the panel, but stops when sunlight is absent) lead to discovery (light energy is being transferred from the sun to activate the solar panel).
1. Show the class the solar propeller. Without explaining how it works, allow students to see how sunlight striking the solar panel makes the propeller spin. Cover up the solar panel with your hand to make it stop.
Teacher NoTe: If it is a sunny day with patchy clouds, simply set the unit in a window and allow students to figure out on their own that the propeller spins rapidly when the sun shines and slows down or even stops when passing clouds block the sun.
2. Discuss where the propeller gets the energy to spin. (Students should recognize that when light shines on the panel the propeller has the energy to spin and when the light is blocked the propeller no longer has the energy to spin.)
Teacher NoTe: If some students believe that the sun’s or the lamp’s heat rather than its light powers the propeller, you can direct hot air from a hair dryer onto the solar panel to show that heat energy alone does not cause the propeller to spin.
3. Introduce the term energy transfer to describe instances where energy moves from one place or object to another (such as from the sun to the solar panel), or changes from one form to another (such as in the solar panel itself, where light energy is changed to electrical energy). Tell the class that they have three fun science sessions to look forward to—they get to explore energy transfers using toys.
Session 2q Set up the nine energy stations as described in the Teacher
Directions “Setting up the Energy Stations” on pages 95–98. Follow these steps before setting up the stations:
a. Make a copy of the Teacher Master “Energy Station Directions.” Cut along the dotted lines to create separate toy operation directions for each station.
b. Bright, direct sunlight is needed to activate the magic bracelet at Energy Station 9. They will not activate using an incandescent bulb or out of direct sunlight. If sunlight is not available, use the compact fluorescent light bulb and clamp lamp provided in the ExploraGear. Allow time for the light bulb to warm up before sending students to the station.
c. Allow ample time to run through each station after set-up to troubleshoot any problems and ensure that the toys are working properly.
q Copy the Family Link Homework “Toy Box Science” to send home with the students.
Using the Student Reference Book• After Session 1, use Chapter 2 of the student reference book to
reinforce the concept of energy transfers.
• (Optional) At the end of this lesson, refer students to the timeline “A Walk Through Energy History” on page 129–146 of the student reference book. Challenge the class to identify the energy transfers associated with several of the timeline events.
Vocabularyenergy transfer . . . . . When energy moves from one object or
place to another or changes from one form to another.
solar energy . . . . . . . . Energy transferred from the sun. Solar energy travels to Earth through space and provides warmth, light, and energy for plant growth.
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| ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN�6
Introductory Discussion—Modeling How to Map Energy Transfers1. Show students the main components of the solar propeller:
a solar panel, a set of wires, a propeller, and a motor that produces a spinning motion.
2. Solicit students’ ideas while you describe how energy transfers through the components, changing from one form to another to make the propeller spin. Questions to encourage critical thinking include:
• What forms of energy are evident as the solar propeller operates?
• Does energy change from one form to another? If so, in what order?
(Light energy from the sun transfers to the solar cells in the solar panel; in the cells, the light energy is transferred to electrical energy; the electrical energy travels through the wires to the motor, where it is transferred into motion energy.)
3. Using the Overhead Transparency “Mapping Energy Transfers” and an erasable overhead marker, show students how to map the energy transfers that made the solar propeller spin. As you connect the different energy forms on the overhead transparency, have students mirror your mapping on page 4 of their science notebooks. Use the following steps and sample energy map to help with this task.
a. Label shapes with the type of energy involved.
b. Draw arrows to map how energy transfers from one form to another as the solar propeller operates.
c. Write a brief description next to your arrows to add details about the forms of energy involved and how they transfer.
4. Wipe off the overhead transparency and ask for volunteers to map some additional examples of energy transfers. Let students use their own ideas of examples of energy transfers or choose from a list you provide.
• Provide at least one example that could be interpreted a variety of ways, such as a hammer raised to drive in a nail. Encourage alternative interpretations. (Some students might see gravitational energy as the energy source that transfers to motion energy which drives the nail in. Others may cite muscle power—chemical energy—transferring to motion energy to drive the nail in. A few students may suggest that sound energy should be included on the map because of the sound the hammer makes as it hits the nail.)
• Use this activity as an opportunity to reinforce the idea that there isn’t one “correct” answer. The objective is for students to notice how energy changes as things happen.
5. Assign Chapter 2 of the student reference book to reinforce the concept of energy transfers.
Overhead Transparency: “Mapping Energy Transfers”
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��ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN |
Introductory Discussion—Modeling How to Map Energy Transfers1. Show students the main components of the solar propeller:
a solar panel, a set of wires, a propeller, and a motor that produces a spinning motion.
2. Solicit students’ ideas while you describe how energy transfers through the components, changing from one form to another to make the propeller spin. Questions to encourage critical thinking include:
• What forms of energy are evident as the solar propeller operates?
• Does energy change from one form to another? If so, in what order?
(Light energy from the sun transfers to the solar cells in the solar panel; in the cells, the light energy is transferred to electrical energy; the electrical energy travels through the wires to the motor, where it is transferred into motion energy.)
3. Using the Overhead Transparency “Mapping Energy Transfers” and an erasable overhead marker, show students how to map the energy transfers that made the solar propeller spin. As you connect the different energy forms on the overhead transparency, have students mirror your mapping on page 4 of their science notebooks. Use the following steps and sample energy map to help with this task.
a. Label shapes with the type of energy involved.
b. Draw arrows to map how energy transfers from one form to another as the solar propeller operates.
c. Write a brief description next to your arrows to add details about the forms of energy involved and how they transfer.
4. Wipe off the overhead transparency and ask for volunteers to map some additional examples of energy transfers. Let students use their own ideas of examples of energy transfers or choose from a list you provide.
• Provide at least one example that could be interpreted a variety of ways, such as a hammer raised to drive in a nail. Encourage alternative interpretations. (Some students might see gravitational energy as the energy source that transfers to motion energy which drives the nail in. Others may cite muscle power—chemical energy—transferring to motion energy to drive the nail in. A few students may suggest that sound energy should be included on the map because of the sound the hammer makes as it hits the nail.)
• Use this activity as an opportunity to reinforce the idea that there isn’t one “correct” answer. The objective is for students to notice how energy changes as things happen.
5. Assign Chapter 2 of the student reference book to reinforce the concept of energy transfers.
NoTes
| ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN��
SESSIOn 3
Big Idea
Energy can move, or transfer, from place to place. Sometimes it changes form as it transfers.
Reflect and Discuss
Teacher NoTe: Students’ understanding of energy transfers, as evidenced by their energy maps, may vary greatly. Some students may simply map the first and last forms of energy noted rather than any intermediary forms. Others may extend their thinking far beyond the basics, including things like the transfer of the chemical energy in the food they eat to the motion energy of their muscles, which in turn was transferred to the toy during operation. Accept all reasonable explanations and focus on each student’s rationale rather than highlighting a single “correct” energy map for each toy.
SharingInitiate reflections on the energy mapping activity and encourage groups to share their findings.
• What was their favorite toy?
• Which toy was most difficult to figure out? Why was it hard to figure out what kinds of energy transfers made this toy run?
• When was it most clear that energy was being transferred? What made it so obvious?
• Was it always possible to know for sure what kinds of transfers occurred? Why or why not? (No! Students were not directed to open the energy ball, for example, to see what was happening inside.)
• Could they still tell that energy was transferred even when the parts were hidden from view or too hard to understand? How? (Students should recognize that the new forms of energy they observed while operating the toys must mean that energy was transferred—even if the mechanism was unclear.)
• Did they observe energy changing forms at any of the stations? (Yes) Did it always change form? (No) Does energy sometimes change into more than one form? (Yes)
• Were there any stations where the members of their group could not agree on the energy transfers that occurred? (Walk the class through any disputed energy transfers. Allow students to explain their reasoning; dispel misconceptions and help them grasp alternative explanations when appropriate.)
SESSIOn 2
Explore
Mapping Energy Transfers in Toys
Teacher NoTe: Familiarize yourself with the explanations on pages 97–98 of how the more complex toys work.
1. Explain the energy mapping activity and answer any questions. Outline these steps:
a. Take turns with other groups visiting nine energy stations, each set up with a different toy and instructions for operating the toy.
b. At each station, operate the toy, figure out what kinds of energy transfers make the toy work, and create a map of those transfers with the group. (Emphasize the importance of observing the toys in action, taking the time needed to think carefully about what the toys do, and considering the opinions of other group members before mapping the energy transfers.)
c. Complete the energy maps on science notebook pages 5–13. Point out that the students need to fill in the name of the toy being operated at the top of each science notebook page.
d. Use the glossary in the science notebook as needed to review descriptions of any of the energy forms.
MaNageMeNT NoTe: Before dividing the class into groups, decide on a rotation strategy. You can have groups rotate in unison after a set amount of time or allow groups to operate at their own pace, moving on to open stations as they become available.
2. Divide the class into nine groups and direct them to the appropriate stations.
Teacher NoTe: Rotate through the stations as groups visit them. Listen for particularly interesting debates regarding the energy transfers that occur. You may wish to revisit these debates during the reflective discussion.
3. Send home the Family Link “Toy Box Science” to provide students with an opportunity to independently trace the flow of energy through a toy of their choice.
Science Notebook pages 5–13
Teacher Master 41, Family Link
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��ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN |
SESSIOn 3
Big Idea
Energy can move, or transfer, from place to place. Sometimes it changes form as it transfers.
Reflect and Discuss
Teacher NoTe: Students’ understanding of energy transfers, as evidenced by their energy maps, may vary greatly. Some students may simply map the first and last forms of energy noted rather than any intermediary forms. Others may extend their thinking far beyond the basics, including things like the transfer of the chemical energy in the food they eat to the motion energy of their muscles, which in turn was transferred to the toy during operation. Accept all reasonable explanations and focus on each student’s rationale rather than highlighting a single “correct” energy map for each toy.
SharingInitiate reflections on the energy mapping activity and encourage groups to share their findings.
• What was their favorite toy?
• Which toy was most difficult to figure out? Why was it hard to figure out what kinds of energy transfers made this toy run?
• When was it most clear that energy was being transferred? What made it so obvious?
• Was it always possible to know for sure what kinds of transfers occurred? Why or why not? (No! Students were not directed to open the energy ball, for example, to see what was happening inside.)
• Could they still tell that energy was transferred even when the parts were hidden from view or too hard to understand? How? (Students should recognize that the new forms of energy they observed while operating the toys must mean that energy was transferred—even if the mechanism was unclear.)
• Did they observe energy changing forms at any of the stations? (Yes) Did it always change form? (No) Does energy sometimes change into more than one form? (Yes)
• Were there any stations where the members of their group could not agree on the energy transfers that occurred? (Walk the class through any disputed energy transfers. Allow students to explain their reasoning; dispel misconceptions and help them grasp alternative explanations when appropriate.)
SESSIOn 2
Explore
Mapping Energy Transfers in Toys
Teacher NoTe: Familiarize yourself with the explanations on pages 97–98 of how the more complex toys work.
1. Explain the energy mapping activity and answer any questions. Outline these steps:
a. Take turns with other groups visiting nine energy stations, each set up with a different toy and instructions for operating the toy.
b. At each station, operate the toy, figure out what kinds of energy transfers make the toy work, and create a map of those transfers with the group. (Emphasize the importance of observing the toys in action, taking the time needed to think carefully about what the toys do, and considering the opinions of other group members before mapping the energy transfers.)
c. Complete the energy maps on science notebook pages 5–13. Point out that the students need to fill in the name of the toy being operated at the top of each science notebook page.
d. Use the glossary in the science notebook as needed to review descriptions of any of the energy forms.
MaNageMeNT NoTe: Before dividing the class into groups, decide on a rotation strategy. You can have groups rotate in unison after a set amount of time or allow groups to operate at their own pace, moving on to open stations as they become available.
2. Divide the class into nine groups and direct them to the appropriate stations.
Teacher NoTe: Rotate through the stations as groups visit them. Listen for particularly interesting debates regarding the energy transfers that occur. You may wish to revisit these debates during the reflective discussion.
3. Send home the Family Link “Toy Box Science” to provide students with an opportunity to independently trace the flow of energy through a toy of their choice.
NoTes
| ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN�0
Ongoing Learning
Science CenterMaterials: Additional toys that run as a result of energy transfers, living organism setups that demonstrate the transfer of energy, and copies of the overhead transparency “Mapping Energy Transfers”
• Place additional toys that run as a result of energy transfers in the Science Center. Possibilities include a pinwheel, a rubber band-powered airplane, a pull-back car, eye poppers (flexible, vinyl half balls that pop up when you flip them inside-out), a Jack-in-the-box, a hand-powered flashlight (with a tiny electrical generator inside instead of batteries) that is activated when the flashlight handle is squeezed, a toddler’s wooden pounding-bench, wind-up toys, and a lava lamp. Provide extra copies of energy maps for students to fill in as they operate the toys. (Use the Overhead Transparency “Mapping Energy Transfers” with a blank piece of paper placed behind it to make extra copies.) Encourage the class to bring in “energized” toys from home to add to the collection.
• Provide several setups that demonstrate how energy transfers in living things, such as a plant in the sunlight, mushrooms on a log, and a leaf-eating insect in a jar full of leaves. Have extra copies of energy maps available for students to map the energy transfers that occur in each of the setups. (Plant = light to chemical; mushroom = chemical to chemical; leaf-eating insect = chemical [leaf matter] to chemical [insect matter] and motion [insect’s movements])
Family LinkIn the Family Link Homework “Toy Box Science” students are asked to describe the energy transfers that occur when they operate one of their own toys. This Family Link can be used as a formative assessment.
A bonus activity is also described, which encourages interested students to chew a wintergreen-flavored Lifesaver® in a dark room. They observe the light emitted as the candy breaks apart and consider the energy transfer involved, which is motion energy (of the teeth) to light energy.
Teacher NoTe: The actual process is really much more complex and involves molecules and the electric charges within them. As you chew, the chemical bonds of the sugar molecules in the lifesavers are torn apart, producing electrical energy among the pieces. This energy is transferred to other molecules which then give it off as light. This happens with most sugars, but the molecule that supplies the wintergreen flavor causes the process to produce more visible light than usual. Producing light energy by rubbing or crushing certain molecules is known as triboluminescence.
MaintenanceCollect and review the Family Link Homework “Toy Box Science” to see whether students were able to trace the flow of energy in one of their own toys independently.
Synthesizing1. Have the class reflect on the exploration and answer the
following questions to reach the conclusion that every time something happens, energy is being transferred:
• Do they think that energy can make something happen (such as making toys work) without being transferred?
• What do their observations indicate?
2. Help students think of energy transfers outside their classroom experiences. Where else do energy transfers occur? Remind them of the energy transfers they read about in their student reference books, if necessary.
3. (Optional) Build on students’ curiosity and questions about the appearance of energy loss to create a foundation for understanding the conservation of energy in more advanced science classes:
• Did the energy seem to run out of any toys at some stations? (The spinning top, bouncing ball, and dominoes may seem to “run out of energy.)
standards and benchmarks connectionHaving students begin thinking about how “energy can change from one form to another, although in the process some energy is always converted to heat” provides an opportunity to introduce students to The Designed World Standard C (Energy Sources and Use) for grades 6–8. Children will build on this introduction in later grades.
• If a toy’s energy seemed to run out, why do they think this happened? Where did the energy go? (Some students may be able to describe what friction does—“the air slowed down the spinning top.” Reinforce this awareness, pointing out other instances where friction occurs—when they rub their hands back and forth, for example. Help them see that, instead of “running out,” the energy is transferred to heat energy.)
Teacher NoTe: Consider teaching the Further Science Exploration “Friction Produces Heat Energy” to help dispel the notion that energy disappears.
NoTes
�1ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN |
Ongoing Learning
Science CenterMaterials: Additional toys that run as a result of energy transfers, living organism setups that demonstrate the transfer of energy, and copies of the overhead transparency “Mapping Energy Transfers”
• Place additional toys that run as a result of energy transfers in the Science Center. Possibilities include a pinwheel, a rubber band-powered airplane, a pull-back car, eye poppers (flexible, vinyl half balls that pop up when you flip them inside-out), a Jack-in-the-box, a hand-powered flashlight (with a tiny electrical generator inside instead of batteries) that is activated when the flashlight handle is squeezed, a toddler’s wooden pounding-bench, wind-up toys, and a lava lamp. Provide extra copies of energy maps for students to fill in as they operate the toys. (Use the Overhead Transparency “Mapping Energy Transfers” with a blank piece of paper placed behind it to make extra copies.) Encourage the class to bring in “energized” toys from home to add to the collection.
• Provide several setups that demonstrate how energy transfers in living things, such as a plant in the sunlight, mushrooms on a log, and a leaf-eating insect in a jar full of leaves. Have extra copies of energy maps available for students to map the energy transfers that occur in each of the setups. (Plant = light to chemical; mushroom = chemical to chemical; leaf-eating insect = chemical [leaf matter] to chemical [insect matter] and motion [insect’s movements])
Family LinkIn the Family Link Homework “Toy Box Science” students are asked to describe the energy transfers that occur when they operate one of their own toys. This Family Link can be used as a formative assessment.
A bonus activity is also described, which encourages interested students to chew a wintergreen-flavored Lifesaver® in a dark room. They observe the light emitted as the candy breaks apart and consider the energy transfer involved, which is motion energy (of the teeth) to light energy.
Teacher NoTe: The actual process is really much more complex and involves molecules and the electric charges within them. As you chew, the chemical bonds of the sugar molecules in the lifesavers are torn apart, producing electrical energy among the pieces. This energy is transferred to other molecules which then give it off as light. This happens with most sugars, but the molecule that supplies the wintergreen flavor causes the process to produce more visible light than usual. Producing light energy by rubbing or crushing certain molecules is known as triboluminescence.
MaintenanceCollect and review the Family Link Homework “Toy Box Science” to see whether students were able to trace the flow of energy in one of their own toys independently.
Synthesizing1. Have the class reflect on the exploration and answer the
following questions to reach the conclusion that every time something happens, energy is being transferred:
• Do they think that energy can make something happen (such as making toys work) without being transferred?
• What do their observations indicate?
2. Help students think of energy transfers outside their classroom experiences. Where else do energy transfers occur? Remind them of the energy transfers they read about in their student reference books, if necessary.
3. (Optional) Build on students’ curiosity and questions about the appearance of energy loss to create a foundation for understanding the conservation of energy in more advanced science classes:
• Did the energy seem to run out of any toys at some stations? (The spinning top, bouncing ball, and dominoes may seem to “run out of energy.)
standards and benchmarks connectionHaving students begin thinking about how “energy can change from one form to another, although in the process some energy is always converted to heat” provides an opportunity to introduce students to The Designed World Standard C (Energy Sources and Use) for grades 6–8. Children will build on this introduction in later grades.
• If a toy’s energy seemed to run out, why do they think this happened? Where did the energy go? (Some students may be able to describe what friction does—“the air slowed down the spinning top.” Reinforce this awareness, pointing out other instances where friction occurs—when they rub their hands back and forth, for example. Help them see that, instead of “running out,” the energy is transferred to heat energy.)
Teacher NoTe: Consider teaching the Further Science Exploration “Friction Produces Heat Energy” to help dispel the notion that energy disappears.
NoTes
| ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN�2
Energy Transfers and the Food Chain
nature’s recyclers connectionExploring food chains with a focus on energy is an ideal way to build upon a key concept from the Science Companion Level 4 Nature’s Recyclers Unit—the recycling of matter through ecosystems. While the total amount of matter at each level of a food chain remains constant, the energy available at each level diminishes as some chemical energy is transformed into forms such as heat and motion that are no longer available to the next level.
Provide opportunities for students to trace the transfer of chemical energy through the food chain. Focus on the decrease in available chemical energy at each stage in a food chain. Discuss some of the energy transfers that account for this decrease. (Living organisms generate heat—a chemical-to-heat energy transfer. This heat energy is in turn transferred to the organisms’ surroundings, making it unavailable to the next level of the food chain. Some chemical energy is also transferred to motion energy in organisms that move.) See the “Energy Science Library and Web Links” section on pages 42–49 and visit www.sciencecompanion.com/links for a list of suggested books and web sites to support this inquiry.
Friction Produces Heat Energy1. Have students observe the heat that is produced when moving
parts rub against each other and discuss the transfers of heat that take place:
a. Tell them to rub their hands back and forth against each other. What is happening to their hands?
b. Direct them to rub together two sheets of sandpaper in a circular motion, without stopping, for several minutes. Have them compare how the sandpaper feels before and after rubbing. What has changed?
2. To help children understand the significance of friction, discuss why a roller coaster seems to “run out of energy.” Post a picture of a roller coaster (or have students build one!) to further the discussion. Consider questions such as these:
• Why does a roller coaster start at the highest hill?
• Why do the hills of a roller coaster get smaller and smaller?
• What causes the roller coaster to slow down?
• Do the cars “rub” against the air?
• Do the wheels “rub” against the track?
• Based on the earlier hand-rubbing and sandpaper rubbing activities, what should happen to the air and tracks as they “rub against” the cars?
• Would anyone be able to see if the air and the tracks were getting hotter? Could this explain why many things seem to run out of energy?
• Does the roller coaster really “run out of energy” or use energy up, or has its energy just been transferred to less useful forms?
Extending the Lesson
Further Science Explorations
Energy Toys from ScratchProvide students with the materials and instructions for several handmade toys, such as whirligigs, button spinners, and tops. See www.sciencecompanion.com/links for links to web sites that offer simple directions for making these and other toys.
Chemical Energy Fun• Demonstrate the chemical-to-heat energy transfer that occurs
when baking yeast and hydrogen peroxide are mixed:
safeTy NoTe: The chemical component (hydrogen peroxide) used in this extension is a common household item and is not hazardous if used with care. Please check with your supervisor about OSHA or state regulations regarding laboratory practice and chemical storage. Use caution and have the children wear goggles and protective gloves when working with hydrogen peroxide.
a. Pour two ounces of hydrogen peroxide in a medium-sized jar.
b. Place a thermometer into the jar to take an initial temperature reading.
c. Add a teaspoon of granular baking yeast to the jar and provide a continuous report to the class of the change (rapid increase) in temperature.
d. Discuss the increase in temperature. Has the energy in the jar changed forms? How can they tell? (Students should recognize that some of the chemical energy of the yeast and hydrogen peroxide has been transferred to heat energy; this accounts for the increase in temperature.)
e. Talk about anything else the children may notice. What other signs indicate that changes have occurred in the jar? (The mixture will immediately begin to bubble and rise up in the jar.)
• Explore a chemical-to-motion energy transfer that’s a blast! Take students outdoors to make and launch pop rockets. Visit www.sciencecompanion.com/links for links to web sites that offer simple directions for making pop rockets using water, Alka-Seltzer®, and a film canister.
safeTy NoTe: Make sure that students wear safety goggles during this pop rocket activity.
NoTes
�3ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN |
Energy Transfers and the Food Chain
nature’s recyclers connectionExploring food chains with a focus on energy is an ideal way to build upon a key concept from the Science Companion Level 4 Nature’s Recyclers Unit—the recycling of matter through ecosystems. While the total amount of matter at each level of a food chain remains constant, the energy available at each level diminishes as some chemical energy is transformed into forms such as heat and motion that are no longer available to the next level.
Provide opportunities for students to trace the transfer of chemical energy through the food chain. Focus on the decrease in available chemical energy at each stage in a food chain. Discuss some of the energy transfers that account for this decrease. (Living organisms generate heat—a chemical-to-heat energy transfer. This heat energy is in turn transferred to the organisms’ surroundings, making it unavailable to the next level of the food chain. Some chemical energy is also transferred to motion energy in organisms that move.) See the “Energy Science Library and Web Links” section on pages 42–49 and visit www.sciencecompanion.com/links for a list of suggested books and web sites to support this inquiry.
Friction Produces Heat Energy1. Have students observe the heat that is produced when moving
parts rub against each other and discuss the transfers of heat that take place:
a. Tell them to rub their hands back and forth against each other. What is happening to their hands?
b. Direct them to rub together two sheets of sandpaper in a circular motion, without stopping, for several minutes. Have them compare how the sandpaper feels before and after rubbing. What has changed?
2. To help children understand the significance of friction, discuss why a roller coaster seems to “run out of energy.” Post a picture of a roller coaster (or have students build one!) to further the discussion. Consider questions such as these:
• Why does a roller coaster start at the highest hill?
• Why do the hills of a roller coaster get smaller and smaller?
• What causes the roller coaster to slow down?
• Do the cars “rub” against the air?
• Do the wheels “rub” against the track?
• Based on the earlier hand-rubbing and sandpaper rubbing activities, what should happen to the air and tracks as they “rub against” the cars?
• Would anyone be able to see if the air and the tracks were getting hotter? Could this explain why many things seem to run out of energy?
• Does the roller coaster really “run out of energy” or use energy up, or has its energy just been transferred to less useful forms?
Extending the Lesson
Further Science Explorations
Energy Toys from ScratchProvide students with the materials and instructions for several handmade toys, such as whirligigs, button spinners, and tops. See www.sciencecompanion.com/links for links to web sites that offer simple directions for making these and other toys.
Chemical Energy Fun• Demonstrate the chemical-to-heat energy transfer that occurs
when baking yeast and hydrogen peroxide are mixed:
safeTy NoTe: The chemical component (hydrogen peroxide) used in this extension is a common household item and is not hazardous if used with care. Please check with your supervisor about OSHA or state regulations regarding laboratory practice and chemical storage. Use caution and have the children wear goggles and protective gloves when working with hydrogen peroxide.
a. Pour two ounces of hydrogen peroxide in a medium-sized jar.
b. Place a thermometer into the jar to take an initial temperature reading.
c. Add a teaspoon of granular baking yeast to the jar and provide a continuous report to the class of the change (rapid increase) in temperature.
d. Discuss the increase in temperature. Has the energy in the jar changed forms? How can they tell? (Students should recognize that some of the chemical energy of the yeast and hydrogen peroxide has been transferred to heat energy; this accounts for the increase in temperature.)
e. Talk about anything else the children may notice. What other signs indicate that changes have occurred in the jar? (The mixture will immediately begin to bubble and rise up in the jar.)
• Explore a chemical-to-motion energy transfer that’s a blast! Take students outdoors to make and launch pop rockets. Visit www.sciencecompanion.com/links for links to web sites that offer simple directions for making pop rockets using water, Alka-Seltzer®, and a film canister.
safeTy NoTe: Make sure that students wear safety goggles during this pop rocket activity.
NoTes
�4
Language Arts ExtensionHave children interview an older family member or neighbor to find out about the mechanical toys they played with as a child. What energy forms were used to make their toys move? What energy forms are commonly used today to make toys run? Consider organizing the students’ findings into a Venn diagram, comparing and contrasting the toys of “Then” and “Now.”
Social Studies ExtensionResearch toys of the 19th century. See the “Energy Science Library and Web Links” section on pages 42–49 and visit www.sciencecompanion.com/links for a list of suggested books and web sites to support this research.
Art Extensions• Have students create flip-books depicting an energy transfer
such as a sailboat propelled by the wind, a chain of dominoes falling, or a baseball bat hitting a ball.
• Reinforce the concept of wind energy by having students create their own kite designs. Submit students’ designs to the Franklin Institute’s Current Creations Archive. Visit www.sciencecompanion.com/links for further details.
Planning Ahead
For Lesson 4Give yourself enough time in advance of Lesson 4 to collect the materials you’ll need, particularly the large, shallow basin for class demonstrations of the boats and the nine smaller basins individual groups will be using to test their boats. Consider sending home the Teacher Master “Request for Materials” to help you get everything you need to conduct this lesson.
For Lesson �Collect empty 2-liter soda bottles. You will need one per group during Session 1.
| ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN
Teacher DirectionsSetting Up the Energy Stations
MaterialsItem Quantity notes
ExploraGear
Ball 1 (3 extra) To demonstrate the transfer of energy.
Chenille wire 1 To make magic bracelet.
Clamp lamp and bulb (optional) 2 To light magic bracelet or radiometer.
Dominoes 1 set To demonstrate the transfer of energy.
Energy ball 1 To demonstrate the transfer of energy.
Hand-held electrical generator 1 To demonstrate the transfer of energy.
Pop-up toy 4 To demonstrate the transfer of energy.
Radiometer 1 To demonstrate the transfer of energy.
Solar energy beads 1 package To make magic bracelet.
Sparking-wheel toy 1 (3 extra) To demonstrate the transfer of energy.
Spinning tops with lights 2 To demonstrate the transfer of energy.
Toy car, pull-back type (optional) 1 (2 extra) To demonstrate the transfer of energy.
Classroom Supplies
Gift box top, large 1 To contain spinning top.
Light source (flashlight, lamp, or sunlight)
1 To power radiometer.
Paper bag, opaque, medium 1 To shield energy-bead bracelet from light. A lunch bag or gift bag works well.
Screwdriver, small, Phillips head 1 To dismantle one of the spinning tops.
Tape 1 roll To tape shut the energy ball.
Preparing the Toys1. Make the magic bracelet for Energy Station 9. Locate the energy beads and chenille wire provided in the
ExploraGear. Thread the beads through the chenille wire and twist together the ends to create a bracelet large enough for children to slip their hands through.
2. Take apart one of the spinning tops using a Phillips head screwdriver. Save all the pieces so students can see and manipulate the top’s working parts at station 6. Leave it unassembled throughout the exploration.
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Language Arts ExtensionHave children interview an older family member or neighbor to find out about the mechanical toys they played with as a child. What energy forms were used to make their toys move? What energy forms are commonly used today to make toys run? Consider organizing the students’ findings into a Venn diagram, comparing and contrasting the toys of “Then” and “Now.”
Social Studies ExtensionResearch toys of the 19th century. See the “Energy Science Library and Web Links” section on pages 42–49 and visit www.sciencecompanion.com/links for a list of suggested books and web sites to support this research.
Art Extensions• Have students create flip-books depicting an energy transfer
such as a sailboat propelled by the wind, a chain of dominoes falling, or a baseball bat hitting a ball.
• Reinforce the concept of wind energy by having students create their own kite designs. Submit students’ designs to the Franklin Institute’s Current Creations Archive. Visit www.sciencecompanion.com/links for further details.
Planning Ahead
For Lesson 4Give yourself enough time in advance of Lesson 4 to collect the materials you’ll need, particularly the large, shallow basin for class demonstrations of the boats and the nine smaller basins individual groups will be using to test their boats. Consider sending home the Teacher Master “Request for Materials” to help you get everything you need to conduct this lesson.
For Lesson �Collect empty 2-liter soda bottles. You will need one per group during Session 1.
ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN |
Teacher DirectionsSetting Up the Energy Stations
MaterialsItem Quantity notes
ExploraGear
Ball 1 (3 extra) To demonstrate the transfer of energy.
Chenille wire 1 To make magic bracelet.
Clamp lamp and bulb (optional) 2 To light magic bracelet or radiometer.
Dominoes 1 set To demonstrate the transfer of energy.
Energy ball 1 To demonstrate the transfer of energy.
Hand-held electrical generator 1 To demonstrate the transfer of energy.
Pop-up toy 4 To demonstrate the transfer of energy.
Radiometer 1 To demonstrate the transfer of energy.
Solar energy beads 1 package To make magic bracelet.
Sparking-wheel toy 1 (3 extra) To demonstrate the transfer of energy.
Spinning tops with lights 2 To demonstrate the transfer of energy.
Toy car, pull-back type (optional) 1 (2 extra) To demonstrate the transfer of energy.
Classroom Supplies
Gift box top, large 1 To contain spinning top.
Light source (flashlight, lamp, or sunlight)
1 To power radiometer.
Paper bag, opaque, medium 1 To shield energy-bead bracelet from light. A lunch bag or gift bag works well.
Screwdriver, small, Phillips head 1 To dismantle one of the spinning tops.
Tape 1 roll To tape shut the energy ball.
Preparing the Toys1. Make the magic bracelet for Energy Station 9. Locate the energy beads and chenille wire provided in the
ExploraGear. Thread the beads through the chenille wire and twist together the ends to create a bracelet large enough for children to slip their hands through.
2. Take apart one of the spinning tops using a Phillips head screwdriver. Save all the pieces so students can see and manipulate the top’s working parts at station 6. Leave it unassembled throughout the exploration.
�6
Setting Up the StationsSet up the nine energy stations for Session 2 as follows:
• Stagger stations throughout the room, using student desk tops, available counter space, and even open floor space. Any space will do as long as there is enough room for small groups to gather around each toy and operate it.
• Place each toy, along with its directions and any of the additional supplies described in the table below, at the appropriate station.
• After the stations are set up, conduct a trial run through each to make sure that the toys are operating properly. Troubleshoot problems as necessary and feel free to make replacements to ensure student success. (For example, you can trade the pull-back car for a problematic toy.)
Teacher NoTe: The basic energy transfers the children are likely to notice at each station are listed in the following table. While these transfers may be the most obvious, students may notice and include others in their energy maps as well, such as the background noise produced by several of the toys (sound energy).
Station number
Type of Toy Additional Supplies/notes Energy Transfers (Most Evident)
1 Pop-up toy Four pop-up toys are provided. Test these out and select one that pops up consistently and in a reasonable amount of time.
Motion to elastic to motion
2 Dominoes Motion to motion to gravitational to motion…
3 Sparking-wheel
Four sparking wheels are provided.Only put out one at a time that consistently generates sparks when operated. Make sure the students follow the directions for the sparking wheel. If used improperly, the wheel will quickly break.
Motion to heat and light
4 Energy ball Tape the energy ball shut before use.
Chemical (battery) to electrical to light and sound
5 Hand-held electrical generator
Make sure light bulb is inserted and working.
Motion to electrical to light; also motion to sound
6 Spinning tops with light (one intact, one taken apart)
Place the intact spinning top in a large gift box lid and the disassembled top off to the side.
Motion to elastic to motion and light
7 Radiometer Set up this station in sunlight or under the clamp lamp. Mark the station with a “Fragile, Handle with Care” sign.
Light to heat to motion
8 Ball Set up this station on an open area of the floor so that students can bounce the ball.
Gravitational to motion to elastic to motion
Explaining How Some Toys WorkOffer the following explanations for the more complex toys if students want to know more about how they work. You don’t need to present this information to the entire class, unless they are all interested.
• Sparking Wheel—Pumping the wheel creates friction. The friction breaks off tiny pieces of a flammable metal alloy. The friction also generates enough heat (motion to heat) to ignite these metal chips, creating sparks. The sparks are only visible momentarily since they quickly cool down. The sparks may lead some students to conclude that the energy transfer includes electrical energy. You can dispel this notion at your discretion.
• Energy Ball—Inside the energy ball are two batteries connected to a light and sound system. When both metal strips (electrodes) are touched, the electric circuit is completed, allowing electrons to flow through the batteries, the person holding the ball, and the light and sound systems. This flow of electricity makes the ball light up and hum.
• Hand-held Electrical Generator—When a bundle of copper wire (or any other conductor) is moved through a magnetic field, electrical current will start to flow along the wire. Peek through the slots in the metal cylinder inside the generator toy; you can see the copper wire bundles that rotate when the handle is turned. The magnets cannot be seen.
| ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN
��
Setting Up the StationsSet up the nine energy stations for Session 2 as follows:
• Stagger stations throughout the room, using student desk tops, available counter space, and even open floor space. Any space will do as long as there is enough room for small groups to gather around each toy and operate it.
• Place each toy, along with its directions and any of the additional supplies described in the table below, at the appropriate station.
• After the stations are set up, conduct a trial run through each to make sure that the toys are operating properly. Troubleshoot problems as necessary and feel free to make replacements to ensure student success. (For example, you can trade the pull-back car for a problematic toy.)
Teacher NoTe: The basic energy transfers the children are likely to notice at each station are listed in the following table. While these transfers may be the most obvious, students may notice and include others in their energy maps as well, such as the background noise produced by several of the toys (sound energy).
Station number
Type of Toy Additional Supplies/notes Energy Transfers (Most Evident)
1 Pop-up toy Four pop-up toys are provided. Test these out and select one that pops up consistently and in a reasonable amount of time.
Motion to elastic to motion
2 Dominoes Motion to motion to gravitational to motion…
3 Sparking-wheel
Four sparking wheels are provided.Only put out one at a time that consistently generates sparks when operated. Make sure the students follow the directions for the sparking wheel. If used improperly, the wheel will quickly break.
Motion to heat and light
4 Energy ball Tape the energy ball shut before use.
Chemical (battery) to electrical to light and sound
5 Hand-held electrical generator
Make sure light bulb is inserted and working.
Motion to electrical to light; also motion to sound
6 Spinning tops with light (one intact, one taken apart)
Place the intact spinning top in a large gift box lid and the disassembled top off to the side.
Motion to elastic to motion and light
7 Radiometer Set up this station in sunlight or under the clamp lamp. Mark the station with a “Fragile, Handle with Care” sign.
Light to heat to motion
8 Ball Set up this station on an open area of the floor so that students can bounce the ball.
Gravitational to motion to elastic to motion
Station number
Type of Toy Additional Supplies/notes Energy Transfers (Most Evident)
9 Magic bracelet Set up this station in an area with ample sunlight. If sunlight is inadequate on the day you conduct this portion of the lesson, set up this station with a clamp lamp fitted with a compact fluorescent bulb. Make sure to turn the lamp on at least five minutes before students visit this station so that the bulb will be adequately warmed up. Place the pre-assembled bracelet in an opaque paper bag.
Light to chemical
Optional replacement
Pull-back toy car
Motion to elastic (spring) to motion
Explaining How Some Toys WorkOffer the following explanations for the more complex toys if students want to know more about how they work. You don’t need to present this information to the entire class, unless they are all interested.
• Sparking Wheel—Pumping the wheel creates friction. The friction breaks off tiny pieces of a flammable metal alloy. The friction also generates enough heat (motion to heat) to ignite these metal chips, creating sparks. The sparks are only visible momentarily since they quickly cool down. The sparks may lead some students to conclude that the energy transfer includes electrical energy. You can dispel this notion at your discretion.
• Energy Ball—Inside the energy ball are two batteries connected to a light and sound system. When both metal strips (electrodes) are touched, the electric circuit is completed, allowing electrons to flow through the batteries, the person holding the ball, and the light and sound systems. This flow of electricity makes the ball light up and hum.
• Hand-held Electrical Generator—When a bundle of copper wire (or any other conductor) is moved through a magnetic field, electrical current will start to flow along the wire. Peek through the slots in the metal cylinder inside the generator toy; you can see the copper wire bundles that rotate when the handle is turned. The magnets cannot be seen.
NoTes
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NoTes
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• Spinning Top—There is a small metal ball inside the top that acts as a switch. When the top spins, the ball is forced outward, completing the electrical circuit that turns the light on.
light connectionBuild on students’ understanding of sunlight from the Science Companion Level 3 Light Unit by giving them the opportunity to test and discover that solar beads do not change color when exposed to visible light alone (indoor lighting) but do change when exposed to sunlight, suggesting that sunlight contains forms of radiation beyond just visible light.
• Radiometer—The sealed glass bulb maintains a partial vacuum, to reduce air friction. When light hits the metal vanes it reflects off the white sides, but is absorbed as heat energy on the black sides. Air molecules flow around the edges of each vane, from the cooler white side toward the warmer black side, causing the top to spin.
• Magic Bracelet—The beads in this bracelet are solar energy beads. Each bead contains a type of pigment that changes color when exposed to ultraviolet light. Sunlight and the light produced by compact fluorescent bulbs contain both ultraviolet and visible light; the ultraviolet light they contain activates the beads. Visible light alone (such as that provided by typical incandescent lighting) will not change the color of the beads.
Overhead Transparency: “Mapping Energy Transfers” Science Notebook page 5–13
��ENERGY | lEssoN 3 | ENERGY TRaNsfERs: how ENERGY makEs ThiNGs haPPEN |
• Spinning Top—There is a small metal ball inside the top that acts as a switch. When the top spins, the ball is forced outward, completing the electrical circuit that turns the light on.
light connectionBuild on students’ understanding of sunlight from the Science Companion Level 3 Light Unit by giving them the opportunity to test and discover that solar beads do not change color when exposed to visible light alone (indoor lighting) but do change when exposed to sunlight, suggesting that sunlight contains forms of radiation beyond just visible light.
• Radiometer—The sealed glass bulb maintains a partial vacuum, to reduce air friction. When light hits the metal vanes it reflects off the white sides, but is absorbed as heat energy on the black sides. Air molecules flow around the edges of each vane, from the cooler white side toward the warmer black side, causing the top to spin.
• Magic Bracelet—The beads in this bracelet are solar energy beads. Each bead contains a type of pigment that changes color when exposed to ultraviolet light. Sunlight and the light produced by compact fluorescent bulbs contain both ultraviolet and visible light; the ultraviolet light they contain activates the beads. Visible light alone (such as that provided by typical incandescent lighting) will not change the color of the beads.
Teacher Master 3, Assessment 1 Teacher Masters 15–16
Teacher Masters 17–18 Teacher Master 41, Family Link
234
Teacher Background Information
This section provides a detailed overview of energy—its significance in the world around us; the forms it takes; how it transfers from one object to another; how easily it passes through different materials; and how it is harnessed in everyday machines. This introduction is intended to give you background information you may need as you teach the unit; however, it is not necessary to master or present all the content that is offered here. The Key Notes section of each lesson indicates which portion to review prior to teaching the lesson. A preliminary read-through before teaching the unit—to get the big picture—followed by more focused readings before each lesson should help you guide the children in their discoveries about the role of energy in the world around them.
Introduction
Energy: A Unifying ConceptEnergy is integral to our understanding of the world around us. It is at the root of all change. Every time something happens, energy is involved. It is the energy in gasoline that makes an automobile run; the energy added to water that makes it boil; the energy in food that allows us to move and grow; the energy of an exploding stick of dynamite that blasts through solid rock; the energy in the sun’s rays that drives weather and life itself; and the energy of moving water, air, sand, and ice that reshapes the surface of the earth.
What Is Energy?Energy is something we understand through experience. We can feel, see, and hear the energy of a thunderstorm. We know what foods to eat when we need a boost of energy. We are amused by the boundless energy of a puppy. We realize that our garden needs the sun’s energy to grow. Intuitively, we understand that energy makes things happen. Doing work is one way to “make things happen” so it is not surprising that the word energy is derived from the Greek word energeia, meaning “at work.”
Scientific definitions for energy also incorporate the idea of work. One common definition for energy is “the ability to perform
work.” While this definition is meaningful to scientists, it can be problematic for students. For scientists, the concept of “work” has a special meaning—“force applied over a distance.” For students, however, many of the things that energy “makes happen,” such as the soaring of a soccer ball, the flash of a bolt of lightning, or the bounce of a trampoline, are not likely to be considered work.
A common misconception held by students is that energy is a “thing” rather than a property of something. Properties, such as energy, are inherently harder to explain and grasp. Energy has no mass, shape, taste, or odor but it can be measured. It can be felt but not touched. Nonetheless, we can recognize, appreciate, explore, and understand energy without a formal definition. In this unit, children will develop their own “working definition” of energy as they explore the role that energy plays in the world around them.
Forms of EnergyEnergy is best described to children in terms of how they experience it in everyday life. While physicists employ a much stricter and more complex standard for distinguishing energy forms, this unit introduces energy in terms of forms that are accessible to students. Don’t be concerned by the variations you encounter in how energy forms are defined and presented in resource books and videos. In this unit, designed specifically for 5th graders, keeping the categories of energy forms simple and recognizable will help students focus on energy’s importance in the world around them.
Two Major Kinds of Energy: Energy in Action and Stored EnergyOne basic way to think about energy is to categorize it into two major forms: energy in action and stored energy (energy not yet in use).
Energy in action is energy in the “act” of bringing about change. Where there is action there is motion. To account for the many different ways that motion is manifested, a variety of energy forms can be considered forms of energy in action.
Stored energy, also referred to as potential energy, is the energy possessed by something but not yet bringing about change. Stored energy results from the position of an object and the forces which are acting on it. Like energy in action, stored or potential energy can be considered to exist in several forms.
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Teacher Background Information
This section provides a detailed overview of energy—its significance in the world around us; the forms it takes; how it transfers from one object to another; how easily it passes through different materials; and how it is harnessed in everyday machines. This introduction is intended to give you background information you may need as you teach the unit; however, it is not necessary to master or present all the content that is offered here. The Key Notes section of each lesson indicates which portion to review prior to teaching the lesson. A preliminary read-through before teaching the unit—to get the big picture—followed by more focused readings before each lesson should help you guide the children in their discoveries about the role of energy in the world around them.
Introduction
Energy: A Unifying ConceptEnergy is integral to our understanding of the world around us. It is at the root of all change. Every time something happens, energy is involved. It is the energy in gasoline that makes an automobile run; the energy added to water that makes it boil; the energy in food that allows us to move and grow; the energy of an exploding stick of dynamite that blasts through solid rock; the energy in the sun’s rays that drives weather and life itself; and the energy of moving water, air, sand, and ice that reshapes the surface of the earth.
What Is Energy?Energy is something we understand through experience. We can feel, see, and hear the energy of a thunderstorm. We know what foods to eat when we need a boost of energy. We are amused by the boundless energy of a puppy. We realize that our garden needs the sun’s energy to grow. Intuitively, we understand that energy makes things happen. Doing work is one way to “make things happen” so it is not surprising that the word energy is derived from the Greek word energeia, meaning “at work.”
Scientific definitions for energy also incorporate the idea of work. One common definition for energy is “the ability to perform
work.” While this definition is meaningful to scientists, it can be problematic for students. For scientists, the concept of “work” has a special meaning—“force applied over a distance.” For students, however, many of the things that energy “makes happen,” such as the soaring of a soccer ball, the flash of a bolt of lightning, or the bounce of a trampoline, are not likely to be considered work.
A common misconception held by students is that energy is a “thing” rather than a property of something. Properties, such as energy, are inherently harder to explain and grasp. Energy has no mass, shape, taste, or odor but it can be measured. It can be felt but not touched. Nonetheless, we can recognize, appreciate, explore, and understand energy without a formal definition. In this unit, children will develop their own “working definition” of energy as they explore the role that energy plays in the world around them.
Forms of EnergyEnergy is best described to children in terms of how they experience it in everyday life. While physicists employ a much stricter and more complex standard for distinguishing energy forms, this unit introduces energy in terms of forms that are accessible to students. Don’t be concerned by the variations you encounter in how energy forms are defined and presented in resource books and videos. In this unit, designed specifically for 5th graders, keeping the categories of energy forms simple and recognizable will help students focus on energy’s importance in the world around them.
Two Major Kinds of Energy: Energy in Action and Stored EnergyOne basic way to think about energy is to categorize it into two major forms: energy in action and stored energy (energy not yet in use).
Energy in action is energy in the “act” of bringing about change. Where there is action there is motion. To account for the many different ways that motion is manifested, a variety of energy forms can be considered forms of energy in action.
Stored energy, also referred to as potential energy, is the energy possessed by something but not yet bringing about change. Stored energy results from the position of an object and the forces which are acting on it. Like energy in action, stored or potential energy can be considered to exist in several forms.
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As discussed, these two major forms of energy—energy in action and stored energy—can each be broken down into several representative energy forms. The table below shows the two major categories and their representative energy forms.
Energy in Action Stored EnergyMotion energy Chemical (potential) energy
Heat energy Elastic (potential) energy
Light energy Gravitational (potential) energy
Electrical energy Nuclear energy
Sound energy
While “energy in action” and “stored energy” are used in the introductory and final lessons as “umbrellas” for students to group examples of energy under, the children are not expected to accurately specify each form as energy in action or stored energy. At this level, the children do not have the background necessary to understand why certain forms (particularly electrical, heat, sound, and light energy) are representative of one category or another. However, in this teacher’s introduction, we have categorized each form of energy in this way so you can relate the material to other sources, and have this broader understanding as you teach.
The frequently used terms “kinetic energy” and “potential energy” are not used in the lessons though you are likely to encounter them in other books and resources about energy. Kinetic energy, however, should technically not be applied to all forms of energy associated with motion. It is exclusively the energy of motion of matter (objects with mass or weight). Several of the energy forms presented under “Energy in Action” involve the movement of “mass-less” entities, such as waves and fields, and cannot be accurately categorized as kinetic energy. Furthermore, chemical energy and nuclear energy involve behavior of things at the atomic level and cannot be described by the usual concepts of kinetic and potential energy.
Energy in Action
Motion Energy
common misconceptionsStudents usually understand how moving things are energized and how their own bodies have energy. They have a more difficult time recognizing more abstract forms of energy, such as light, electricity, and elastic energy.
Motion energy, often referred to as kinetic energy, is the energy present in moving objects or materials, such as the wind or falling water. Motion energy is the most easily recognizable form of energy. When you see a speeding car, a soaring baseball, a rushing river, or a towering twister, the energy they possess is unmistakable. These examples embody change—energy is clearly at work.
We depend on motion energy to get us from place to place, chew our food, drive nails into walls, and power windmills and water turbines.
Heat Energy
The terms “heat,” “heat energy,” and “thermal energy” are synonymous. As you teach, whenever possible, reinforce that heat is energy to help dispel the common misconception that heat is a thing rather than a property of a substance. Using the term “heat energy” may help make this distinction but students should be aware that the term “heat,” so widely used in everyday life, also refers to “heat energy.”
For the students we define “heat energy” as the energy which an object has as a result of its temperature. At a more sophisticated level, heat, also known as thermal energy, is a consequence of motion. In this case, the particles moving are the minute atoms and molecules found within all substances. The faster these particles move the more heat energy a substance possesses.
Since the students may not know about atoms and molecules or the connection between their motion and heat, they are unlikely to associate heat energy with motion. For them, heat energy will be just a form of energy associated with an object’s temperature.
We depend on heat energy to cook our food, warm our homes and dry our clothes. In engines (gas, diesel, or steam) heat energy produced by burning fuels is transferred into energy of motion. Heat energy is also used in many power plants to generate electricity.
Students may confuse the terms heat energy and temperature. Whenever possible, reinforce to children that the heat energy of an object is not the same thing as its temperature. The amount of heat energy an object possesses depends not only on temperature—a measure of how hot or cold something is—but also on the mass of the object and on the type of matter from which it is formed. It is clear, for example, that a bathtub of water at 35oC (95oF) holds more heat energy than a glass of water at the same temperature. Comparing, or asking children to compare, how much heat energy would have to be added to a cold glass of water and a bathtub full of cold water to allow each to reach a temperature of 35oC may help to clarify this point.
One common source of heat energy is friction—the resistance that occurs whenever two substances rub against each other. While the heat energy resulting from friction is desirable when you are rubbing your hands together to stay warm, it is less desirable when the moving parts of your car’s engine heat up.
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As discussed, these two major forms of energy—energy in action and stored energy—can each be broken down into several representative energy forms. The table below shows the two major categories and their representative energy forms.
Energy in Action Stored EnergyMotion energy Chemical (potential) energy
Heat energy Elastic (potential) energy
Light energy Gravitational (potential) energy
Electrical energy Nuclear energy
Sound energy
While “energy in action” and “stored energy” are used in the introductory and final lessons as “umbrellas” for students to group examples of energy under, the children are not expected to accurately specify each form as energy in action or stored energy. At this level, the children do not have the background necessary to understand why certain forms (particularly electrical, heat, sound, and light energy) are representative of one category or another. However, in this teacher’s introduction, we have categorized each form of energy in this way so you can relate the material to other sources, and have this broader understanding as you teach.
The frequently used terms “kinetic energy” and “potential energy” are not used in the lessons though you are likely to encounter them in other books and resources about energy. Kinetic energy, however, should technically not be applied to all forms of energy associated with motion. It is exclusively the energy of motion of matter (objects with mass or weight). Several of the energy forms presented under “Energy in Action” involve the movement of “mass-less” entities, such as waves and fields, and cannot be accurately categorized as kinetic energy. Furthermore, chemical energy and nuclear energy involve behavior of things at the atomic level and cannot be described by the usual concepts of kinetic and potential energy.
Energy in Action
Motion Energy
common misconceptionsStudents usually understand how moving things are energized and how their own bodies have energy. They have a more difficult time recognizing more abstract forms of energy, such as light, electricity, and elastic energy.
Motion energy, often referred to as kinetic energy, is the energy present in moving objects or materials, such as the wind or falling water. Motion energy is the most easily recognizable form of energy. When you see a speeding car, a soaring baseball, a rushing river, or a towering twister, the energy they possess is unmistakable. These examples embody change—energy is clearly at work.
We depend on motion energy to get us from place to place, chew our food, drive nails into walls, and power windmills and water turbines.
Heat Energy
The terms “heat,” “heat energy,” and “thermal energy” are synonymous. As you teach, whenever possible, reinforce that heat is energy to help dispel the common misconception that heat is a thing rather than a property of a substance. Using the term “heat energy” may help make this distinction but students should be aware that the term “heat,” so widely used in everyday life, also refers to “heat energy.”
For the students we define “heat energy” as the energy which an object has as a result of its temperature. At a more sophisticated level, heat, also known as thermal energy, is a consequence of motion. In this case, the particles moving are the minute atoms and molecules found within all substances. The faster these particles move the more heat energy a substance possesses.
Since the students may not know about atoms and molecules or the connection between their motion and heat, they are unlikely to associate heat energy with motion. For them, heat energy will be just a form of energy associated with an object’s temperature.
We depend on heat energy to cook our food, warm our homes and dry our clothes. In engines (gas, diesel, or steam) heat energy produced by burning fuels is transferred into energy of motion. Heat energy is also used in many power plants to generate electricity.
Students may confuse the terms heat energy and temperature. Whenever possible, reinforce to children that the heat energy of an object is not the same thing as its temperature. The amount of heat energy an object possesses depends not only on temperature—a measure of how hot or cold something is—but also on the mass of the object and on the type of matter from which it is formed. It is clear, for example, that a bathtub of water at 35oC (95oF) holds more heat energy than a glass of water at the same temperature. Comparing, or asking children to compare, how much heat energy would have to be added to a cold glass of water and a bathtub full of cold water to allow each to reach a temperature of 35oC may help to clarify this point.
One common source of heat energy is friction—the resistance that occurs whenever two substances rub against each other. While the heat energy resulting from friction is desirable when you are rubbing your hands together to stay warm, it is less desirable when the moving parts of your car’s engine heat up.
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Light EnergyFor the students we define “light energy” as the energy carried by light rays. On a more sophisticated level, light energy, also known as radiant energy, is the energy carried by electromagnetic waves—waves of energy traveling through matter or empty space.
While there are many types of electromagnetic waves—such as radio waves, microwaves, infrared waves, visible light, ultraviolet light, and x-rays—in this unit, light energy will primarily be equated with visible light, since that is the type most likely to be recognized by students. For example, the energy from the sun is referred to simply as light, even though it is actually a more complex combination of visible light, ultraviolet light, and infrared waves. If students in your class studied the Science Companion Level 3 Light Unit, you can refer back to what they learned about visible light in that unit and pursue discussions about other types of electromagnetic waves if the children bring them up.
All life ultimately depends on light energy. Plants harness the energy in sunlight to produce the food that supports all other living things, and sunlight warms the earth, maintaining surface temperatures that sustain life. The energy in light also makes photography possible and, when concentrated into special beams of light called lasers, is powerful enough to drill through metals and cut through tissue during surgery.
Electrical EnergyAll matter consists of minute building blocks called atoms. Atoms are composed of even smaller particles: a central nucleus consisting of protons (each with a positive electric charge) and neutrons (with a “neutral” charge—no electric charge), that is surrounded by a cloud of electrons (with negative electric charges). Electrically charged particles operate under an “opposites attract” principle.
Since (negatively charged) electrons are attracted to substances or regions with a net positive electric charge (which just means there are more protons than electrons in the region), they will naturally flow toward these regions when free to do so. In conductors—most metals, for example—some electrons are free to flow through the material because they are held loosely by their atoms. These flowing electrons possess electrical energy—they are capable of performing work and bringing about change.
Since the children have not yet learned that an electric current is a stream of moving particles, they are not likely to associate electrical energy with motion. At this stage, it’s sufficient for them to know that electrical energy is a type of energy associated with electric current.
The electricity (electrons flowing through a wire or another conductor) that powers household appliances—toasters, lights, refrigerators, computers, dishwashers, televisions, etc.—demonstrates the work that can be performed by electrical energy. A tree felled by a bolt of lightning is another familiar reminder of the power of electrical energy. In this case, there is so much electrical energy in the lightning bolt that it overcomes wood’s natural resistance to the flow of electrons (wood is usually an “insulator,” or non-conductor).
Children merely need to recognize examples of electrical energy in this unit. They should not be expected to know what is happening on a molecular level.
Sound EnergySound is carried through substances in waves of vibrating (back and forth moving) molecules. Where there is movement there is energy—the vibrating molecules that make up sound waves therefore possess energy. When sound waves hit the ear drum, they energize the eardrum which causes it to vibrate. The vibrating eardrum ultimately triggers messages to the brain (as vibrations pass from the eardrum to the bones of the middle ear to the fluid and tiny sensory hairs of the inner ear) that are the basis for hearing.
If students in your class studied the Science Companion Level 2 Sound Unit, you can refer back to what they learned about sound and vibrations in that unit.
Stored Energy
Chemical (Potential) EnergyChemical energy is the energy stored in chemical substances, such as fuel or food. All substances are made up of atoms and molecules. These atoms and molecules are connected to one another (held together) by attractive forces known as chemical bonds.
The attraction between positively and negatively charged particles is the “glue” that holds all matter together, allowing atoms to bind together to form molecules ranging from relatively simple molecules (such as pure metals) to very complex structures (such as proteins and DNA).
When the bonds between atoms and molecules rearrange, as they do during chemical reactions (such as burning), there is frequently a net release of energy. This potential for bond rearrangement and net energy release via chemical reactions is the basis for chemical energy. Even though it takes energy to break chemical bonds,
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Light EnergyFor the students we define “light energy” as the energy carried by light rays. On a more sophisticated level, light energy, also known as radiant energy, is the energy carried by electromagnetic waves—waves of energy traveling through matter or empty space.
While there are many types of electromagnetic waves—such as radio waves, microwaves, infrared waves, visible light, ultraviolet light, and x-rays—in this unit, light energy will primarily be equated with visible light, since that is the type most likely to be recognized by students. For example, the energy from the sun is referred to simply as light, even though it is actually a more complex combination of visible light, ultraviolet light, and infrared waves. If students in your class studied the Science Companion Level 3 Light Unit, you can refer back to what they learned about visible light in that unit and pursue discussions about other types of electromagnetic waves if the children bring them up.
All life ultimately depends on light energy. Plants harness the energy in sunlight to produce the food that supports all other living things, and sunlight warms the earth, maintaining surface temperatures that sustain life. The energy in light also makes photography possible and, when concentrated into special beams of light called lasers, is powerful enough to drill through metals and cut through tissue during surgery.
Electrical EnergyAll matter consists of minute building blocks called atoms. Atoms are composed of even smaller particles: a central nucleus consisting of protons (each with a positive electric charge) and neutrons (with a “neutral” charge—no electric charge), that is surrounded by a cloud of electrons (with negative electric charges). Electrically charged particles operate under an “opposites attract” principle.
Since (negatively charged) electrons are attracted to substances or regions with a net positive electric charge (which just means there are more protons than electrons in the region), they will naturally flow toward these regions when free to do so. In conductors—most metals, for example—some electrons are free to flow through the material because they are held loosely by their atoms. These flowing electrons possess electrical energy—they are capable of performing work and bringing about change.
Since the children have not yet learned that an electric current is a stream of moving particles, they are not likely to associate electrical energy with motion. At this stage, it’s sufficient for them to know that electrical energy is a type of energy associated with electric current.
The electricity (electrons flowing through a wire or another conductor) that powers household appliances—toasters, lights, refrigerators, computers, dishwashers, televisions, etc.—demonstrates the work that can be performed by electrical energy. A tree felled by a bolt of lightning is another familiar reminder of the power of electrical energy. In this case, there is so much electrical energy in the lightning bolt that it overcomes wood’s natural resistance to the flow of electrons (wood is usually an “insulator,” or non-conductor).
Children merely need to recognize examples of electrical energy in this unit. They should not be expected to know what is happening on a molecular level.
Sound EnergySound is carried through substances in waves of vibrating (back and forth moving) molecules. Where there is movement there is energy—the vibrating molecules that make up sound waves therefore possess energy. When sound waves hit the ear drum, they energize the eardrum which causes it to vibrate. The vibrating eardrum ultimately triggers messages to the brain (as vibrations pass from the eardrum to the bones of the middle ear to the fluid and tiny sensory hairs of the inner ear) that are the basis for hearing.
If students in your class studied the Science Companion Level 2 Sound Unit, you can refer back to what they learned about sound and vibrations in that unit.
Stored Energy
Chemical (Potential) EnergyChemical energy is the energy stored in chemical substances, such as fuel or food. All substances are made up of atoms and molecules. These atoms and molecules are connected to one another (held together) by attractive forces known as chemical bonds.
The attraction between positively and negatively charged particles is the “glue” that holds all matter together, allowing atoms to bind together to form molecules ranging from relatively simple molecules (such as pure metals) to very complex structures (such as proteins and DNA).
When the bonds between atoms and molecules rearrange, as they do during chemical reactions (such as burning), there is frequently a net release of energy. This potential for bond rearrangement and net energy release via chemical reactions is the basis for chemical energy. Even though it takes energy to break chemical bonds,
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if new, more stable (less energetic) bonds form, more energy is released than is used.
Substances, such as dynamite, made up of atoms and molecules bound together by high-energy, less stable bonds, are a rich source of chemical energy. As their high-energy bonds are broken and more stable, lower-energy bonds form, significant amounts of energy are freed up and released. Burning (combustion) is a familiar chemical reaction that results in the release of chemical energy. When the chemicals in materials such as wood “burn.” their chemical bonds rearrange—high-energy bonds (in the wood) are broken and more stable, lower-energy bonds (in the products of burning such as CO2 and H2O) form. The difference in energy between these low and high energy bonds accounts for the release of energy you feel when wood is burned.
common misconceptionStudents may find it strange to consider food a chemical, since—in general usage—a chemical may be something they are warned never to eat.
Petroleum, natural gas, coal, and propane are burned to release the stored chemical energy that powers our cars, planes, and trains, heats and cools our homes, and generates the electricity that keeps our lives “humming.” We depend on the chemical energy in food to allow our bodies to grow and function. We blast through mountains using the chemical energy in dynamite and harness the chemical energy in gunpowder to light up the skies on holidays.
Elastic (Potential) EnergyElastic energy is the energy stored when elastic materials are stretched or compressed. Materials that demonstrate elasticity, such as rubber bands and springs, can be deformed but naturally revert to their original shape when the force causing the deformation is removed. As the materials return to their original shape, the energy that was used to stretch or compress them is released and can be used to perform work (although some of the energy is released as heat).
Slingshots, bows and arrows, wind-up toys, bungee cords, winding clocks, and balloons demonstrate some of the ways that the energy of deformed (compressed or stretched) materials is stored and then used to produce motion or do work.
Gravitational (Potential) EnergyAll matter is attracted to other matter by the force of gravity. The more massive and closer one object is to another, the more gravitational force it exerts. On Earth, it is the planet itself—as a consequence of its massive size and proximity—that is the predominant source of gravitational attraction. Earth exerts a continuous pull on all objects within its domain or gravitational field. (In addition to Earth’s pull, all objects at or near Earth’s surface—by virtue of their mass—also exert gravitational pull on
each other. However, because the Earth is so massive relative to these objects, their gravitational pull is negligible.)
Energy is required to move an object against Earth’s gravitational pull. When you push a large boulder up a hill or throw a ball in the air, you use energy to move against Earth’s gravitational attraction. The energy expended to move the ball and boulder away from Earth’s center of gravity is now “stored” by virtue of the object’s new position relative to Earth’s gravitational field. Give the boulder a slight nudge and you will see its stored gravitational energy put to work clearing a path as it thunders down the hill. The heavier an object is and the higher it is raised, the more gravitational energy it possesses (and the more energy it took to get it there). A massive boulder teetering at the top of a hill has much more gravitational energy than a pebble poised at the same spot, and a ball raised to a height of 100 meters (109.4 yards) has more gravitational energy than it would have if it was raised to a height of only10 meters (10.94 yards).
Water behind a dam represents a huge “reservoir” of gravitational energy. Hydroelectric power plants capitalize on this potential energy, releasing the water behind a dam in controlled flows to spin huge turbines that produce electricity. Gravitational energy also gives raised hammers their extra “punch” and provides the “thrill” that people seek when they board a roller coaster.
Nuclear Energy
Students are not explicitly introduced to nuclear energy in this unit. If you live in an area supplied by a nuclear power plant or have students who are interested in nuclear energy, you may want to introduce the following information, in a simple form, to the class.
Nuclear energy is the energy stored in the dense central region of atoms known as the nucleus. It is released whenever heavy unstable nuclei (the plural form of nucleus) break down (fission) or whenever light nuclei combine (fusion). During fission and fusion a minute quantity of the atom’s mass is actually changed into a very large amount of energy. Einstein’s famous equation E = mc2, in which E stands for energy, m for mass, and c for the speed of light (about 300,000 kilometers per second or 186,000 miles per second) describes this phenomenon.
The energy from the sun that sustains life on Earth is based on the fusion of nuclei in the sun’s core and the subsequent release of nuclear energy. The controlled fission of uranium nuclei provides electricity at nuclear power plants and the uncontrolled chain-reaction fission of uranium and plutonium nuclei gives atomic bombs their destructive power.
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if new, more stable (less energetic) bonds form, more energy is released than is used.
Substances, such as dynamite, made up of atoms and molecules bound together by high-energy, less stable bonds, are a rich source of chemical energy. As their high-energy bonds are broken and more stable, lower-energy bonds form, significant amounts of energy are freed up and released. Burning (combustion) is a familiar chemical reaction that results in the release of chemical energy. When the chemicals in materials such as wood “burn.” their chemical bonds rearrange—high-energy bonds (in the wood) are broken and more stable, lower-energy bonds (in the products of burning such as CO2 and H2O) form. The difference in energy between these low and high energy bonds accounts for the release of energy you feel when wood is burned.
common misconceptionStudents may find it strange to consider food a chemical, since—in general usage—a chemical may be something they are warned never to eat.
Petroleum, natural gas, coal, and propane are burned to release the stored chemical energy that powers our cars, planes, and trains, heats and cools our homes, and generates the electricity that keeps our lives “humming.” We depend on the chemical energy in food to allow our bodies to grow and function. We blast through mountains using the chemical energy in dynamite and harness the chemical energy in gunpowder to light up the skies on holidays.
Elastic (Potential) EnergyElastic energy is the energy stored when elastic materials are stretched or compressed. Materials that demonstrate elasticity, such as rubber bands and springs, can be deformed but naturally revert to their original shape when the force causing the deformation is removed. As the materials return to their original shape, the energy that was used to stretch or compress them is released and can be used to perform work (although some of the energy is released as heat).
Slingshots, bows and arrows, wind-up toys, bungee cords, winding clocks, and balloons demonstrate some of the ways that the energy of deformed (compressed or stretched) materials is stored and then used to produce motion or do work.
Gravitational (Potential) EnergyAll matter is attracted to other matter by the force of gravity. The more massive and closer one object is to another, the more gravitational force it exerts. On Earth, it is the planet itself—as a consequence of its massive size and proximity—that is the predominant source of gravitational attraction. Earth exerts a continuous pull on all objects within its domain or gravitational field. (In addition to Earth’s pull, all objects at or near Earth’s surface—by virtue of their mass—also exert gravitational pull on
each other. However, because the Earth is so massive relative to these objects, their gravitational pull is negligible.)
Energy is required to move an object against Earth’s gravitational pull. When you push a large boulder up a hill or throw a ball in the air, you use energy to move against Earth’s gravitational attraction. The energy expended to move the ball and boulder away from Earth’s center of gravity is now “stored” by virtue of the object’s new position relative to Earth’s gravitational field. Give the boulder a slight nudge and you will see its stored gravitational energy put to work clearing a path as it thunders down the hill. The heavier an object is and the higher it is raised, the more gravitational energy it possesses (and the more energy it took to get it there). A massive boulder teetering at the top of a hill has much more gravitational energy than a pebble poised at the same spot, and a ball raised to a height of 100 meters (109.4 yards) has more gravitational energy than it would have if it was raised to a height of only10 meters (10.94 yards).
Water behind a dam represents a huge “reservoir” of gravitational energy. Hydroelectric power plants capitalize on this potential energy, releasing the water behind a dam in controlled flows to spin huge turbines that produce electricity. Gravitational energy also gives raised hammers their extra “punch” and provides the “thrill” that people seek when they board a roller coaster.
Nuclear Energy
Students are not explicitly introduced to nuclear energy in this unit. If you live in an area supplied by a nuclear power plant or have students who are interested in nuclear energy, you may want to introduce the following information, in a simple form, to the class.
Nuclear energy is the energy stored in the dense central region of atoms known as the nucleus. It is released whenever heavy unstable nuclei (the plural form of nucleus) break down (fission) or whenever light nuclei combine (fusion). During fission and fusion a minute quantity of the atom’s mass is actually changed into a very large amount of energy. Einstein’s famous equation E = mc2, in which E stands for energy, m for mass, and c for the speed of light (about 300,000 kilometers per second or 186,000 miles per second) describes this phenomenon.
The energy from the sun that sustains life on Earth is based on the fusion of nuclei in the sun’s core and the subsequent release of nuclear energy. The controlled fission of uranium nuclei provides electricity at nuclear power plants and the uncontrolled chain-reaction fission of uranium and plutonium nuclei gives atomic bombs their destructive power.
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Transfer of EnergyEnergy is constantly moving from place to place and changing forms to make things happen.
Transformation of EnergySome of the energy transfers students explore will demonstrate energy changing from one form to another—energy transformations—while others will simply show energy moving from one object to another without changing form. Children are not asked to distinguish between these different types of transfers, so the term “transformation” is not presented as a unit student vocabulary word.
Transfers of energy involving change of form are referred to as energy transformations. (In this unit, they are simply called energy transfers.) Energy transformations are a constant in the world around us. Discussing some of the following examples will help children see that energy transfers and transformations are fundamental to almost everything that happens.
Energy Transformation
Example(s)
Light to Heat Children know that a blazing sun makes their popsicles melt, the asphalt “burn,” and the inside of their cars stifling. They intuitively understand that the light energy in the sun’s rays is transformed to heat energy at Earth’s surface.
Heat to Light The glow that results when the metal coils of stovetops, ovens, toasters, and incandescent light bulbs are heated is a familiar example of the transformation of heat energy to light energy.
Heat to Motion The warmth provided by the sun is the driving force behind Earth’s winds—demonstrating a familiar example of the transformation of heat energy to the motion energy of air. Likewise, heat energy from deep within the Earth’s core is the driving force between such violent events as earthquakes and volcanic eruptions.
When heat energy moves from a burner to a pan to the water in the pan, the water eventually boils. The movement apparent in the boiling water again demonstrates the transformation of heat energy to motion energy.
Energy Transformation
Example(s)
Motion to Heat The moving parts of your car’s engine heat up as they slide past each other. This phenomenon results from friction, the force that resists movement. It demonstrates how motion energy can be transformed to heat energy.
Chemical to Light Glowsticks, fireworks, and matches demonstrate the transformation of chemical energy to light energy.
Light to Chemical The energy in sunlight is transformed into chemical energy by plants through the process of photosynthesis. Special pigments in plant leaves absorb the sun’s energy and use it to create the sugars the plants need to grow and function. (Plants, in turn, provide food [chemical] energy for humans and other organisms.)
Light energy also makes photography possible. Light, entering the camera as a picture is “shot,” strikes the film causing the silver salts coating the film to turn black (a chemical change) and produce a negative image.
Light to Electrical Solar panels are devices that harness light’s energy to produce electricity. Solar panels function like batteries, providing the electrons necessary to create an electric current. Solar panels are essentially collections of solar cells (referred to as photovoltaics, meaning “light-electricity”) that function by giving up electrons when struck by light. The “free” electrons provide the electrical current that powers an ever-expanding array of solar devices including calculators, parking meters, refrigerators, home heating and cooling systems, and satellites in space.
Electrical to Light Fluorescent lamps and LED lights are familiar examples of the transformation of electrical energy into light energy.
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Transfer of EnergyEnergy is constantly moving from place to place and changing forms to make things happen.
Transformation of EnergySome of the energy transfers students explore will demonstrate energy changing from one form to another—energy transformations—while others will simply show energy moving from one object to another without changing form. Children are not asked to distinguish between these different types of transfers, so the term “transformation” is not presented as a unit student vocabulary word.
Transfers of energy involving change of form are referred to as energy transformations. (In this unit, they are simply called energy transfers.) Energy transformations are a constant in the world around us. Discussing some of the following examples will help children see that energy transfers and transformations are fundamental to almost everything that happens.
Energy Transformation
Example(s)
Light to Heat Children know that a blazing sun makes their popsicles melt, the asphalt “burn,” and the inside of their cars stifling. They intuitively understand that the light energy in the sun’s rays is transformed to heat energy at Earth’s surface.
Heat to Light The glow that results when the metal coils of stovetops, ovens, toasters, and incandescent light bulbs are heated is a familiar example of the transformation of heat energy to light energy.
Heat to Motion The warmth provided by the sun is the driving force behind Earth’s winds—demonstrating a familiar example of the transformation of heat energy to the motion energy of air. Likewise, heat energy from deep within the Earth’s core is the driving force between such violent events as earthquakes and volcanic eruptions.
When heat energy moves from a burner to a pan to the water in the pan, the water eventually boils. The movement apparent in the boiling water again demonstrates the transformation of heat energy to motion energy.
Energy Transformation
Example(s)
Motion to Heat The moving parts of your car’s engine heat up as they slide past each other. This phenomenon results from friction, the force that resists movement. It demonstrates how motion energy can be transformed to heat energy.
Chemical to Light Glowsticks, fireworks, and matches demonstrate the transformation of chemical energy to light energy.
Light to Chemical The energy in sunlight is transformed into chemical energy by plants through the process of photosynthesis. Special pigments in plant leaves absorb the sun’s energy and use it to create the sugars the plants need to grow and function. (Plants, in turn, provide food [chemical] energy for humans and other organisms.)
Light energy also makes photography possible. Light, entering the camera as a picture is “shot,” strikes the film causing the silver salts coating the film to turn black (a chemical change) and produce a negative image.
Light to Electrical Solar panels are devices that harness light’s energy to produce electricity. Solar panels function like batteries, providing the electrons necessary to create an electric current. Solar panels are essentially collections of solar cells (referred to as photovoltaics, meaning “light-electricity”) that function by giving up electrons when struck by light. The “free” electrons provide the electrical current that powers an ever-expanding array of solar devices including calculators, parking meters, refrigerators, home heating and cooling systems, and satellites in space.
Electrical to Light Fluorescent lamps and LED lights are familiar examples of the transformation of electrical energy into light energy.
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Energy Transformation
Example(s)
Sound to Electrical/ Electrical to Sound
A microphone converts sound energy to electrical energy. When you speak into a microphone the energy possessed by the sound waves “carrying” your voice causes a membrane within the microphone to move. The moving membrane causes an attached magnet to move within a coil, resulting in the generation of an electric current. The reverse process occurs to translate this electric current to the amplified sound of your voice emanating from a loudspeaker.
Sound waves of high frequencies, known as ultrasound, allow us to peer inside the human body or find hairline cracks in the metal of an airplane’s wing. Ultrasound machines direct high-frequency sound waves towards a tissue, organ, or object under analysis. The sound waves, bouncing back from the structure like an echo, are converted into electrical energy by a computer and then translated into a detailed image for study.
Motion to Gravitational/ Gravitational to Motion
A baseball hit high into left field, a football kicked over a field goal, and a child pushed to the high point of a swing all show the gravitational energy that can be gained through motion.
A sled descending a hill, a kayak riding the rapids, and a tree falling in the forest are examples of gravitational energy being converted to motion.
Swings and pendulums demonstrate the cyclic transformation of energy from motion energy to gravitational energy and from gravitational energy back to motion energy, over and over again.
Energy Transformation
Example(s)
Motion to Elastic/Elastic to Motion (plus Gravitational)
Children have abundant firsthand experience with the transformation of motion energy to elastic energy and elastic energy back to motion energy. Rubber bands and rubber band gliders, slingshots, catapults, and pop-up toys are some of the ways that children discover how stretching or compressing elastic objects stores elastic energy that produces motion when released.
(With bouncing toys and equipment such as trampolines and pogo sticks, gravitational energy also plays a role. A cycle of energy transformations repeats with each bounce: elastic energy is transformed to motion energy [the bounce]; motion energy is transformed to gravitational [potential] energy [the child rising]; gravitational energy is transformed to motion energy [the child falling]; motion energy is transformed to elastic energy [the child landing and compressing the pogo stick spring or stretching the trampoline]. This process repeats itself again and again.)
Electrical to Heat Toasters, electric ranges, and ovens demonstrate how the energy in electricity can be converted to the heat energy that cooks our food.
Electrical to Motion The moving parts of household appliances, such as the blades of a fan, the beaters of a mixer, or the agitator in a washing machine, demonstrate how the energy in electricity can be converted into the energy of motion.
Motion to Sound Plucking a guitar string, tapping a drum, vibrating our vocal chords, and playing the piano are some of the ways that motion is transformed into sound.
Chemical to Electrical The batteries in our cars, cell phones, flashlights, and portable MP3 players demonstrate how chemical energy can be converted to electrical energy. Within batteries, a chemical reaction supplies free electrons. The electrons collect on the negative end or terminal of the battery. If a connection is made between the negative and positive terminals—in many devices, this occurs when a switch is flipped—the electrons will flow from the negative to the positive terminal, creating the electrical current that makes cell phones and other battery-operated devices run.
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Energy Transformation
Example(s)
Sound to Electrical/ Electrical to Sound
A microphone converts sound energy to electrical energy. When you speak into a microphone the energy possessed by the sound waves “carrying” your voice causes a membrane within the microphone to move. The moving membrane causes an attached magnet to move within a coil, resulting in the generation of an electric current. The reverse process occurs to translate this electric current to the amplified sound of your voice emanating from a loudspeaker.
Sound waves of high frequencies, known as ultrasound, allow us to peer inside the human body or find hairline cracks in the metal of an airplane’s wing. Ultrasound machines direct high-frequency sound waves towards a tissue, organ, or object under analysis. The sound waves, bouncing back from the structure like an echo, are converted into electrical energy by a computer and then translated into a detailed image for study.
Motion to Gravitational/ Gravitational to Motion
A baseball hit high into left field, a football kicked over a field goal, and a child pushed to the high point of a swing all show the gravitational energy that can be gained through motion.
A sled descending a hill, a kayak riding the rapids, and a tree falling in the forest are examples of gravitational energy being converted to motion.
Swings and pendulums demonstrate the cyclic transformation of energy from motion energy to gravitational energy and from gravitational energy back to motion energy, over and over again.
Energy Transformation
Example(s)
Motion to Elastic/Elastic to Motion (plus Gravitational)
Children have abundant firsthand experience with the transformation of motion energy to elastic energy and elastic energy back to motion energy. Rubber bands and rubber band gliders, slingshots, catapults, and pop-up toys are some of the ways that children discover how stretching or compressing elastic objects stores elastic energy that produces motion when released.
(With bouncing toys and equipment such as trampolines and pogo sticks, gravitational energy also plays a role. A cycle of energy transformations repeats with each bounce: elastic energy is transformed to motion energy [the bounce]; motion energy is transformed to gravitational [potential] energy [the child rising]; gravitational energy is transformed to motion energy [the child falling]; motion energy is transformed to elastic energy [the child landing and compressing the pogo stick spring or stretching the trampoline]. This process repeats itself again and again.)
Electrical to Heat Toasters, electric ranges, and ovens demonstrate how the energy in electricity can be converted to the heat energy that cooks our food.
Electrical to Motion The moving parts of household appliances, such as the blades of a fan, the beaters of a mixer, or the agitator in a washing machine, demonstrate how the energy in electricity can be converted into the energy of motion.
Motion to Sound Plucking a guitar string, tapping a drum, vibrating our vocal chords, and playing the piano are some of the ways that motion is transformed into sound.
Chemical to Electrical The batteries in our cars, cell phones, flashlights, and portable MP3 players demonstrate how chemical energy can be converted to electrical energy. Within batteries, a chemical reaction supplies free electrons. The electrons collect on the negative end or terminal of the battery. If a connection is made between the negative and positive terminals—in many devices, this occurs when a switch is flipped—the electrons will flow from the negative to the positive terminal, creating the electrical current that makes cell phones and other battery-operated devices run.
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Energy Transformation
Example(s)
Chemical to Motion The transformation of chemical energy to the energy of motion gets us from place to place. From the fuels that power our cars, buses, trucks, planes, and trains, to the “fuel” that powers our muscle cells, chemical energy is being harnessed to get us where we want to go. In most engines the chemical energy is first turned to heat; the heat energy is then transformed into motion energy.
Chemical to Heat (to Motion to Electrical)
The burning of wood or fuel (coal and oil, for example) demonstrates how energy stored in chemical bonds can be converted to heat.
(Many power plants use the heat energy produced when fuels such as coal, oil, and natural gas are burned to boil water and create steam. In turn, the steam is used to turn huge turbines. These turbines are used to generate electricity.)
Transforming Energy from One Form to Severalcommon misconceptionStudents often think that one form of energy can only be changed to one other form rather than to multiple forms.
Many transfers of energy involve the transformation of energy from one form to several forms. Some of the examples listed in the table above demonstrate this point. Burning a log converts the chemical energy possessed by its wood into light, heat, and even sound energy (the sound of a crackling fireplace). The electrical energy of a toaster is transformed not only into the heat energy that toasts your bread, but also into the light energy evident in its glowing coils. The gravitational energy possessed by a roller coaster at the top of a hill is converted into the motion energy of its descending cars, the heat energy (resulting from friction) of its tracks and wheels, and the sound energy of its rattling cars and rails.
In Lesson 3, students discover this phenomenon firsthand as they map the energy transfers that occur when they operate a variety of toys. A number of these toys will show energy being transformed from one form to several. (In fact, since some of the energy used to operate each toy is transformed to heat energy, all the toys actually demonstrate the transformation of energy from one form to several. Students, however, are unlikely to make this connection since the amount of heat energy generated is virtually imperceptible.)
Machines: Making Use of Energy TransfersMany of the examples of energy transformations cited in the table involve machines. Toasters, ovens, ranges, fans, washing machines, refrigerators, computers, calculators, and engines are just some of the many machines that we rely on to make our lives easier. Machines are designed to facilitate the energy transfers necessary to make something specific occur. In Lesson 4, students will design boat “machines” that transfer a variety of energy forms (chemical, elastic, and motion) to make their boats “go.” They will also read in their student reference books about the energy transfers that occur to make some real boats “go.”
Sailboats work by capturing the wind in their sails. As the wind is caught, its motion energy is transferred to the motion energy of the boat, moving it across the water.
Rowboats, canoes, and kayaks rely on muscle power (and the water’s current) to propel them forward. The chemical energy in a paddler’s or rower’s muscles are used to move their arms. The motion energy of their arms is transferred to the oars and paddles, and eventually to the boat itself, moving it where they want it to go.
Power boats operate by burning fuel (gasoline or diesel). As the fuel is burned in the motor, the heat energy produced is usually transferred to the motion energy of a spinning propeller. As the propeller spins, it pushes the water backwards, moving the boat forward.
Machines and the Spirit of InventionAnother theme running through this unit is the spirit of invention. Over the course of this unit, students contemplate the design of various machines, become familiar with several well-known inventors, build machines that utilize energy transfers themselves, and even design their own inventions.
Heat TransferEnergy does not always change form as it moves from object to object or place to place. This is particularly evident with heat energy. To bring about the chemical changes we associate with “cooked” food, heat flows from the burner on your stove to the pan resting upon it, and then to the food it contains. Heat flows from campfires to campers’ marshmallows. It flows from the sand warmed by the sun to the air above it, creating onshore sea breezes.
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Energy Transformation
Example(s)
Chemical to Motion The transformation of chemical energy to the energy of motion gets us from place to place. From the fuels that power our cars, buses, trucks, planes, and trains, to the “fuel” that powers our muscle cells, chemical energy is being harnessed to get us where we want to go. In most engines the chemical energy is first turned to heat; the heat energy is then transformed into motion energy.
Chemical to Heat (to Motion to Electrical)
The burning of wood or fuel (coal and oil, for example) demonstrates how energy stored in chemical bonds can be converted to heat.
(Many power plants use the heat energy produced when fuels such as coal, oil, and natural gas are burned to boil water and create steam. In turn, the steam is used to turn huge turbines. These turbines are used to generate electricity.)
Transforming Energy from One Form to Severalcommon misconceptionStudents often think that one form of energy can only be changed to one other form rather than to multiple forms.
Many transfers of energy involve the transformation of energy from one form to several forms. Some of the examples listed in the table above demonstrate this point. Burning a log converts the chemical energy possessed by its wood into light, heat, and even sound energy (the sound of a crackling fireplace). The electrical energy of a toaster is transformed not only into the heat energy that toasts your bread, but also into the light energy evident in its glowing coils. The gravitational energy possessed by a roller coaster at the top of a hill is converted into the motion energy of its descending cars, the heat energy (resulting from friction) of its tracks and wheels, and the sound energy of its rattling cars and rails.
In Lesson 3, students discover this phenomenon firsthand as they map the energy transfers that occur when they operate a variety of toys. A number of these toys will show energy being transformed from one form to several. (In fact, since some of the energy used to operate each toy is transformed to heat energy, all the toys actually demonstrate the transformation of energy from one form to several. Students, however, are unlikely to make this connection since the amount of heat energy generated is virtually imperceptible.)
Machines: Making Use of Energy TransfersMany of the examples of energy transformations cited in the table involve machines. Toasters, ovens, ranges, fans, washing machines, refrigerators, computers, calculators, and engines are just some of the many machines that we rely on to make our lives easier. Machines are designed to facilitate the energy transfers necessary to make something specific occur. In Lesson 4, students will design boat “machines” that transfer a variety of energy forms (chemical, elastic, and motion) to make their boats “go.” They will also read in their student reference books about the energy transfers that occur to make some real boats “go.”
Sailboats work by capturing the wind in their sails. As the wind is caught, its motion energy is transferred to the motion energy of the boat, moving it across the water.
Rowboats, canoes, and kayaks rely on muscle power (and the water’s current) to propel them forward. The chemical energy in a paddler’s or rower’s muscles are used to move their arms. The motion energy of their arms is transferred to the oars and paddles, and eventually to the boat itself, moving it where they want it to go.
Power boats operate by burning fuel (gasoline or diesel). As the fuel is burned in the motor, the heat energy produced is usually transferred to the motion energy of a spinning propeller. As the propeller spins, it pushes the water backwards, moving the boat forward.
Machines and the Spirit of InventionAnother theme running through this unit is the spirit of invention. Over the course of this unit, students contemplate the design of various machines, become familiar with several well-known inventors, build machines that utilize energy transfers themselves, and even design their own inventions.
Heat TransferEnergy does not always change form as it moves from object to object or place to place. This is particularly evident with heat energy. To bring about the chemical changes we associate with “cooked” food, heat flows from the burner on your stove to the pan resting upon it, and then to the food it contains. Heat flows from campfires to campers’ marshmallows. It flows from the sand warmed by the sun to the air above it, creating onshore sea breezes.
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How Does Heat Flow?
common misconceptionStudents often think that cool objects such as ice transfer their “coolness” to warmer objects, instead of realizing what actually happens—that warmer objects transfer some of their heat energy to cooler ones.
Heat energy spontaneously flows from hot items to cold ones. If two objects are at different temperatures, heat will naturally flow from the warmer object to the cooler one until both objects are at the same temperature.
The transfer of heat from a warmer object to a cooler one occurs in one (or more) of three different ways: conduction, convection, and radiation.
• Conduction is the most common way heat is transferred through solid materials. When a metal spoon is placed in a bowl of hot soup, it is through conduction that the exposed handle heats up. On a microscopic level, heat energy is being transferred by direct contact, from one molecule to the next, through the spoon all the way up to the handle. The molecules in the spoon closest to a heat source—those in the portion of the spoon submerged in the hot soup—vibrate faster and collide more frequently with nearby molecules, causing heat energy to be transferred up the spoon to the top of the handle with each collision. Substances that allow heat to travel through them are called conductors. Good conductors tend to be dense and include metals such as copper, silver, gold, and aluminum. Poor conductors, known as insulators, include plastic, rubber, air, and wood.
common misconceptionSome children may think that heat rises. It is hot air that rises, not heat. While students are not expected to understand that it is the energized particles (molecules) of “heated” air or a liquid that are rising and not “heat” itself, try to avoid using terms and phrases that might reinforce this misconception.
• Convection is the transfer of heat that occurs when the heated material itself moves from one place to another. Heat is transferred through fluids—liquids and gases (in a positive gravitational field such as Earth’s) through convection. The molecules in fluids (remember, this means gases too!) are free to move about. This means that energized molecules can move from one location to another, “carrying” their heat energy with them. When the molecules of a fluid gain heat energy, they move faster and “spread out.” As these heated molecules spread out they become less dense than nearby “unheated” molecules. Cooler, denser regions of the fluid settle beneath the warmer, less dense regions, pushing the warm regions up and out of the way. The temperature difference between a home’s attic and basement demonstrates this phenomenon—warm air rises and collects in the attic, while cooler, denser air settles in the basement.
In the presence of a constant heat source, such as the burner of a stove or the sun’s light, heat is transferred and ultimately circulated through convection currents. Fluids warmed by the heat source become less dense and rise; they are replaced by cooler, denser fluids which, in turn, are warmed and then replaced. This cycle continues, generating the convection currents that redistribute heat from its source. The impact
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of convection currents on Earth is far-reaching, with wind, ocean currents, and the movement of Earth’s tectonic plates ultimately resulting from this kind of cycle.
• Radiation is the transfer of heat from a distance through electromagnetic waves (infrared, visible, or ultraviolet radiation). All objects (above 0 degrees Kelvin) possess some heat energy and thus emit electromagnetic radiation. Very hot objects like the sun emit higher energy waves—visible and ultraviolet light. Cooler objects emit lower energy infrared radiation. Electromagnetic waves travel without molecular “couriers” (in a vacuum—in the absence of matter) at the speed of light through space. When we bask in the warmth of the sun from a distance of 150 million kilometers (93,205,700 miles), we experience this phenomenon.
The properties of an object—such as its color, texture, and reflectivity—determine whether the radiation striking it will be absorbed or reflected. Radiated heat, commonly referred to as radiant heat, is transferred most readily to and from objects that are dull, dark in color, and rough in texture. Conversely, objects that are shiny, smooth, and light-colored are more likely to reflect radiant heat.
Heat Transfer and EfficiencyThe transfer of heat, flowing from hotter objects or areas to colder ones, cooks our food, warms and cools our homes, and dries our clothes. The fact that heat is always on the move also means that the heat energy tends to dissipate, meaning it spreads out, becoming unavailable for useful purposes. When you tell children to close the door on a cold winter’s day to keep the heat in, or to do the same on a hot summer’s day to keep the heat out, you are acknowledging this fact.
All devices produce heat. Some do it by design, such as toasters and ovens. Others, such as light bulbs and gas-powered engines, do so unavoidably; the heat produced serves no useful function. The heat released by these devices eventually dissipates and is not recaptured for further use. Dissipated heat represents inefficiency. Since no machine is 100% efficient (not even close!), ultimately some of the energy cycled through a machine will dissipate as heat energy. Devices that minimize heat loss are considered more energy-efficient than those that don’t. Because they waste less heat, energy-efficient devices use less energy overall to perform the same job.
Friction is the force that resists movement. Since all machines have moving parts, all machines are subject to friction. Friction results in the transfer of some of a machine’s motion energy to heat energy. This heat usually serves no purpose and is considered “wasted” energy.
24�
How Does Heat Flow?
common misconceptionStudents often think that cool objects such as ice transfer their “coolness” to warmer objects, instead of realizing what actually happens—that warmer objects transfer some of their heat energy to cooler ones.
Heat energy spontaneously flows from hot items to cold ones. If two objects are at different temperatures, heat will naturally flow from the warmer object to the cooler one until both objects are at the same temperature.
The transfer of heat from a warmer object to a cooler one occurs in one (or more) of three different ways: conduction, convection, and radiation.
• Conduction is the most common way heat is transferred through solid materials. When a metal spoon is placed in a bowl of hot soup, it is through conduction that the exposed handle heats up. On a microscopic level, heat energy is being transferred by direct contact, from one molecule to the next, through the spoon all the way up to the handle. The molecules in the spoon closest to a heat source—those in the portion of the spoon submerged in the hot soup—vibrate faster and collide more frequently with nearby molecules, causing heat energy to be transferred up the spoon to the top of the handle with each collision. Substances that allow heat to travel through them are called conductors. Good conductors tend to be dense and include metals such as copper, silver, gold, and aluminum. Poor conductors, known as insulators, include plastic, rubber, air, and wood.
common misconceptionSome children may think that heat rises. It is hot air that rises, not heat. While students are not expected to understand that it is the energized particles (molecules) of “heated” air or a liquid that are rising and not “heat” itself, try to avoid using terms and phrases that might reinforce this misconception.
• Convection is the transfer of heat that occurs when the heated material itself moves from one place to another. Heat is transferred through fluids—liquids and gases (in a positive gravitational field such as Earth’s) through convection. The molecules in fluids (remember, this means gases too!) are free to move about. This means that energized molecules can move from one location to another, “carrying” their heat energy with them. When the molecules of a fluid gain heat energy, they move faster and “spread out.” As these heated molecules spread out they become less dense than nearby “unheated” molecules. Cooler, denser regions of the fluid settle beneath the warmer, less dense regions, pushing the warm regions up and out of the way. The temperature difference between a home’s attic and basement demonstrates this phenomenon—warm air rises and collects in the attic, while cooler, denser air settles in the basement.
In the presence of a constant heat source, such as the burner of a stove or the sun’s light, heat is transferred and ultimately circulated through convection currents. Fluids warmed by the heat source become less dense and rise; they are replaced by cooler, denser fluids which, in turn, are warmed and then replaced. This cycle continues, generating the convection currents that redistribute heat from its source. The impact
of convection currents on Earth is far-reaching, with wind, ocean currents, and the movement of Earth’s tectonic plates ultimately resulting from this kind of cycle.
• Radiation is the transfer of heat from a distance through electromagnetic waves (infrared, visible, or ultraviolet radiation). All objects (above 0 degrees Kelvin) possess some heat energy and thus emit electromagnetic radiation. Very hot objects like the sun emit higher energy waves—visible and ultraviolet light. Cooler objects emit lower energy infrared radiation. Electromagnetic waves travel without molecular “couriers” (in a vacuum—in the absence of matter) at the speed of light through space. When we bask in the warmth of the sun from a distance of 150 million kilometers (93,205,700 miles), we experience this phenomenon.
The properties of an object—such as its color, texture, and reflectivity—determine whether the radiation striking it will be absorbed or reflected. Radiated heat, commonly referred to as radiant heat, is transferred most readily to and from objects that are dull, dark in color, and rough in texture. Conversely, objects that are shiny, smooth, and light-colored are more likely to reflect radiant heat.
Heat Transfer and EfficiencyThe transfer of heat, flowing from hotter objects or areas to colder ones, cooks our food, warms and cools our homes, and dries our clothes. The fact that heat is always on the move also means that the heat energy tends to dissipate, meaning it spreads out, becoming unavailable for useful purposes. When you tell children to close the door on a cold winter’s day to keep the heat in, or to do the same on a hot summer’s day to keep the heat out, you are acknowledging this fact.
All devices produce heat. Some do it by design, such as toasters and ovens. Others, such as light bulbs and gas-powered engines, do so unavoidably; the heat produced serves no useful function. The heat released by these devices eventually dissipates and is not recaptured for further use. Dissipated heat represents inefficiency. Since no machine is 100% efficient (not even close!), ultimately some of the energy cycled through a machine will dissipate as heat energy. Devices that minimize heat loss are considered more energy-efficient than those that don’t. Because they waste less heat, energy-efficient devices use less energy overall to perform the same job.
Friction is the force that resists movement. Since all machines have moving parts, all machines are subject to friction. Friction results in the transfer of some of a machine’s motion energy to heat energy. This heat usually serves no purpose and is considered “wasted” energy.
ENERGY | TEaChER baCkGRouNd iNfoRmaTioN |
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In Lesson 8, students will investigate energy efficiency as they compare compact fluorescent bulbs and incandescent bulbs. They will discover that incandescent bulbs release more heat energy than comparable compact fluorescent bulbs using the same amount of electrical energy.
Incandescent bulbs contain a filament that glows, producing light when heated. Electricity is used to heat the filament. Compact fluorescent bulbs contain a gas that becomes energized as electricity passes through it. The energized gas reacts with a coating on the inside of the bulb to produce light. 27w
100w
Compact fluorescent bulbs transform electrical energy into light more efficiently. If the same amount of energy input is supplied to both bulbs, a compact fluorescent bulb will produce more light output, or lumens, and less heat than an incandescent light bulb. In fact, about 90% of the electricity used by incandescent bulbs is “lost” as heat. Comparing the relative wattage—a measure of the electrical energy a light bulb uses per second—and lumens shows that compact fluorescent bulbs use about one-fourth the energy of incandescent bulbs while delivering the same amount of light. An 18-Watt compact fluorescent, for example, produces the same amount of light as a 75-Watt incandescent light bulb—meaning 57 fewer watts are used. Not only are compact fluorescent bulbs more efficient, they also last about ten times longer than incandescent bulbs. While compact fluorescent bulbs may cost more than incandescent light bulbs to purchase, their overall savings—in terms of operating expenses and energy conservation—should be weighed.
While CFLs are presented as the energy-efficient light bulb alternative in Lesson 8, they are not the only alternative. LEDs, for example, are also becoming widespread. LED stands for Light Emitting Diode. LEDs last a very long time (tens of thousands of hours). They are also extremely energy-efficient and durable. While LEDs are still too expensive for everyday use, they are often used in locations where it’s hard to change a light bulb, such as traffic signal lights, tail lights of automobiles, and business signs.
Limiting the Transfer of HeatMaximizing energy efficiency translates into lower operating expenses and a “cleaner” environment.
The current reliance on fossil fuels to “run” our homes, offices, cars, planes, and trains has an environmental cost—the burning of fossil fuels is a major source of air pollutants such as carbon dioxide, carbon monoxide, sulfur dioxide, and nitrogen oxides. Mining practices also have a detrimental environmental impact. Strip mining practices used to extract coal, for example, have led to filling in wetlands; and drainage of acid runoff from these mines harms nearby rivers and streams.
New technologies, such as compact fluorescent light bulbs, limit the dissipation of heat, saving consumers money, decreasing the demand for electricity, and resulting in less environmental damage.
While CFLs use less electricity, they are not totally environment “friendly.” They contain the heavy metal mercury which can pose an environmental threat if not disposed of properly. Students are presented with the pros and cons of many energy alternatives in their student reference books.
The relative heat conductivity of the materials used to make various items is also a key factor in limiting heat dissipation. Students discover this in Lesson 7 as they test a variety of materials to see which material or combination of materials is most effective at keeping heat energy from escaping a bottle of warm water.
Using Insulators to Limit Heat TransferAs indicated earlier, materials that are conductors (primarily metals) allow heat to flow through them easily, while materials that are insulators (rubber, wood, air, and plastic) limit the transfer of heat.
Trapping Air to Limit Heat TransferGases are good insulators because they are not dense and their molecules are relatively far apart. This is why humans will suffer from hypothermia after just a few minutes in 50oF water, but not in 50oF air. (Water is about 1,000 times as dense as air and is much more effective at conducting away body heat.)
Trapped air is a particularly effective insulator—trapped air cannot circulate and, consequently, cannot transfer heat by convection. Many insulating materials are designed to capitalize on this quality.
• Fiberglass insulation is made of glass spun into very fine, air-trapping fibers. (Think of the air pockets in spun cotton candy.) While glass is a relatively good conductor, fiberglass, which is made of long thin pieces of glass, does not conduct well. This characteristic, combined with fiberglass’ ability to trap air between its fibers, makes fiberglass an excellent insulator. Fiberglass blankets are sandwiched between the walls of most homes to keep them cool in the summer (keeping heat energy out) and warm in the winter (keeping heat energy in).
• Like fiberglass, foam makes use of trapped air to keep our hot drinks hot, and our cold drinks cold. Foam is formed
| ENERGY | TEaChER baCkGRouNd iNfoRmaTioN
2�1
In Lesson 8, students will investigate energy efficiency as they compare compact fluorescent bulbs and incandescent bulbs. They will discover that incandescent bulbs release more heat energy than comparable compact fluorescent bulbs using the same amount of electrical energy.
Incandescent bulbs contain a filament that glows, producing light when heated. Electricity is used to heat the filament. Compact fluorescent bulbs contain a gas that becomes energized as electricity passes through it. The energized gas reacts with a coating on the inside of the bulb to produce light. 27w
100w
Compact fluorescent bulbs transform electrical energy into light more efficiently. If the same amount of energy input is supplied to both bulbs, a compact fluorescent bulb will produce more light output, or lumens, and less heat than an incandescent light bulb. In fact, about 90% of the electricity used by incandescent bulbs is “lost” as heat. Comparing the relative wattage—a measure of the electrical energy a light bulb uses per second—and lumens shows that compact fluorescent bulbs use about one-fourth the energy of incandescent bulbs while delivering the same amount of light. An 18-Watt compact fluorescent, for example, produces the same amount of light as a 75-Watt incandescent light bulb—meaning 57 fewer watts are used. Not only are compact fluorescent bulbs more efficient, they also last about ten times longer than incandescent bulbs. While compact fluorescent bulbs may cost more than incandescent light bulbs to purchase, their overall savings—in terms of operating expenses and energy conservation—should be weighed.
While CFLs are presented as the energy-efficient light bulb alternative in Lesson 8, they are not the only alternative. LEDs, for example, are also becoming widespread. LED stands for Light Emitting Diode. LEDs last a very long time (tens of thousands of hours). They are also extremely energy-efficient and durable. While LEDs are still too expensive for everyday use, they are often used in locations where it’s hard to change a light bulb, such as traffic signal lights, tail lights of automobiles, and business signs.
Limiting the Transfer of HeatMaximizing energy efficiency translates into lower operating expenses and a “cleaner” environment.
The current reliance on fossil fuels to “run” our homes, offices, cars, planes, and trains has an environmental cost—the burning of fossil fuels is a major source of air pollutants such as carbon dioxide, carbon monoxide, sulfur dioxide, and nitrogen oxides. Mining practices also have a detrimental environmental impact. Strip mining practices used to extract coal, for example, have led to filling in wetlands; and drainage of acid runoff from these mines harms nearby rivers and streams.
New technologies, such as compact fluorescent light bulbs, limit the dissipation of heat, saving consumers money, decreasing the demand for electricity, and resulting in less environmental damage.
While CFLs use less electricity, they are not totally environment “friendly.” They contain the heavy metal mercury which can pose an environmental threat if not disposed of properly. Students are presented with the pros and cons of many energy alternatives in their student reference books.
The relative heat conductivity of the materials used to make various items is also a key factor in limiting heat dissipation. Students discover this in Lesson 7 as they test a variety of materials to see which material or combination of materials is most effective at keeping heat energy from escaping a bottle of warm water.
Using Insulators to Limit Heat TransferAs indicated earlier, materials that are conductors (primarily metals) allow heat to flow through them easily, while materials that are insulators (rubber, wood, air, and plastic) limit the transfer of heat.
Trapping Air to Limit Heat TransferGases are good insulators because they are not dense and their molecules are relatively far apart. This is why humans will suffer from hypothermia after just a few minutes in 50oF water, but not in 50oF air. (Water is about 1,000 times as dense as air and is much more effective at conducting away body heat.)
Trapped air is a particularly effective insulator—trapped air cannot circulate and, consequently, cannot transfer heat by convection. Many insulating materials are designed to capitalize on this quality.
• Fiberglass insulation is made of glass spun into very fine, air-trapping fibers. (Think of the air pockets in spun cotton candy.) While glass is a relatively good conductor, fiberglass, which is made of long thin pieces of glass, does not conduct well. This characteristic, combined with fiberglass’ ability to trap air between its fibers, makes fiberglass an excellent insulator. Fiberglass blankets are sandwiched between the walls of most homes to keep them cool in the summer (keeping heat energy out) and warm in the winter (keeping heat energy in).
• Like fiberglass, foam makes use of trapped air to keep our hot drinks hot, and our cold drinks cold. Foam is formed
ENERGY | TEaChER baCkGRouNd iNfoRmaTioN |
| ENERGY | TEaChER baCkGRouNd iNfoRmaTioN 2�2
by blowing air into plastic (an insulator) to create a solid substance filled with air pockets.
• The high-tech insulators known as aerogels (also known as frozen smoke due to their appearance) are extremely porous silica structures made almost entirely of air (99.8 percent), making them phenomenal insulators.
• Wintry fabrics such as wool, fur, and synthetic fleece are valued for their ability to trap the air that keeps body heat from escaping. Layering clothing also effectively traps air (pockets of air get trapped between each layer of clothing) and limits the loss of body heat.
• Wood, a natural insulator with millions of tiny pores and air pockets, is a common insulating material used in windows, doors, and cooking utensils.
Using Reflective Materials to Limit Heat TransferReflectivity is another important characteristic that influences the degree of heat transfer. Reflective materials are incorporated into many products because they reflect rather than absorb radiated heat:
• People often wear white clothing to stay cool in the summer. Light colors reflect more radiant heat and visible light than dark colors, which absorb radiant heat and light.
• Fiberglass insulation frequently comes wrapped in a thin reflective foil of aluminum. The aluminum reflects heat back into the home during the winter months and back out of the home during the summer.
• Certain brands of extreme-weather clothing feature a thin plastic film lining that is highly reflective. The film reflects body heat back towards a person’s body rather than allowing it to escape into the surrounding air.
• Thermoses, particularly older models, also feature a reflective coating to limit the transfer of heat between the contents of the thermos and its surroundings.
Conservation of Energy
common misconceptionStudents often think that energy is a fuel-like quantity which is used up, and see machines as one of the ways that energy gets “used up.”
The awareness that energy changes from one form to another and that heat energy dissipates is the key to understanding one of the most basic principles of energy: energy can neither be created nor destroyed. This principle, known as the Conservation of Energy or First Law of Thermodynamics, dispels the notion of energy loss. Many items seem to run out of energy—a kicked ball eventually stops, spinning tops eventually fall over, and bikes screech to a halt when we slam on
the brakes. Encouraging students to trace the flow of energy will help them realize that energy was not lost, but transferred to other places and forms. This realization will provide the foundation for exploring the conservation of energy in later years.
Energy ConservationIf energy is never lost, why do we need to conserve energy? The need to conserve energy is a consequence of the forms of energy available at a given time rather than the total amount of energy present. The current “energy crisis” is due to the fact that energy is being transformed from easy-to-use forms, such as coal and petroleum, into harder-to-use forms, such as heat (which dissipates). At the current rate of consumption, most of the “easy-to-use” fossil fuels that we depend on will be depleted some time in this century. (While coal reserves are larger and not expected to run out for 200 years at the current rate of extraction, once the other fossil fuels are depleted, the rate of coal extraction is expected to increase significantly, thereby accelerating the depletion of coal as well.) Fossil fuels are not considered renewable. They take too long—millions of year!—to re-form. It will ultimately be necessary to shift our dependence from non-renewable forms of energy to renewable forms such as solar (light energy), wind (motion energy), hydropower (gravitational and motion energy), and geothermal (heat and motion energy).
The shift to renewable forms of energy is also seen as a means to protect the environment. The air pollutants produced by fossil-fuel burning power plants and automobiles (including carbon dioxide, methane, sulfuric, and nitrous oxides) contribute to acid rain, global warming, and smog.
Global warming is considered a consequence of the greenhouse effect. When sunlight (light energy) travels through the glass of a greenhouse (or the windows of a car), it is transferred to heat energy—warming up the air and surfaces inside. Unlike light energy, heat energy does not move through glass easily. The glass traps heat energy inside, keeping plants warm enough to live in the winter. Greenhouse gases, such as carbon dioxide, methane, and water vapor, form a layer in the atmosphere that acts in a similar way—allowing sunlight to pass through, but trapping heat energy inside. This is good to a degree—Earth’s average temperature would be much colder without these gases. But problems arise if this layer is allowed to get thicker and thicker, trapping more and more heat, and causing Earth’s temperature to gradually rise. Even a slight rise in Earth’s temperature can have huge consequences.
Acid rain forms when oxides of nitrogen and sulfite—produced primarily by burning fossil fuels—combine with moisture in the atmosphere to make nitric and sulfuric acids. The result is precipitation with a pH level less than 5.6 that adversely affects the regions receiving it. The associated environmental damage over time can be great, including the destruction
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by blowing air into plastic (an insulator) to create a solid substance filled with air pockets.
• The high-tech insulators known as aerogels (also known as frozen smoke due to their appearance) are extremely porous silica structures made almost entirely of air (99.8 percent), making them phenomenal insulators.
• Wintry fabrics such as wool, fur, and synthetic fleece are valued for their ability to trap the air that keeps body heat from escaping. Layering clothing also effectively traps air (pockets of air get trapped between each layer of clothing) and limits the loss of body heat.
• Wood, a natural insulator with millions of tiny pores and air pockets, is a common insulating material used in windows, doors, and cooking utensils.
Using Reflective Materials to Limit Heat TransferReflectivity is another important characteristic that influences the degree of heat transfer. Reflective materials are incorporated into many products because they reflect rather than absorb radiated heat:
• People often wear white clothing to stay cool in the summer. Light colors reflect more radiant heat and visible light than dark colors, which absorb radiant heat and light.
• Fiberglass insulation frequently comes wrapped in a thin reflective foil of aluminum. The aluminum reflects heat back into the home during the winter months and back out of the home during the summer.
• Certain brands of extreme-weather clothing feature a thin plastic film lining that is highly reflective. The film reflects body heat back towards a person’s body rather than allowing it to escape into the surrounding air.
• Thermoses, particularly older models, also feature a reflective coating to limit the transfer of heat between the contents of the thermos and its surroundings.
Conservation of Energy
common misconceptionStudents often think that energy is a fuel-like quantity which is used up, and see machines as one of the ways that energy gets “used up.”
The awareness that energy changes from one form to another and that heat energy dissipates is the key to understanding one of the most basic principles of energy: energy can neither be created nor destroyed. This principle, known as the Conservation of Energy or First Law of Thermodynamics, dispels the notion of energy loss. Many items seem to run out of energy—a kicked ball eventually stops, spinning tops eventually fall over, and bikes screech to a halt when we slam on
the brakes. Encouraging students to trace the flow of energy will help them realize that energy was not lost, but transferred to other places and forms. This realization will provide the foundation for exploring the conservation of energy in later years.
Energy ConservationIf energy is never lost, why do we need to conserve energy? The need to conserve energy is a consequence of the forms of energy available at a given time rather than the total amount of energy present. The current “energy crisis” is due to the fact that energy is being transformed from easy-to-use forms, such as coal and petroleum, into harder-to-use forms, such as heat (which dissipates). At the current rate of consumption, most of the “easy-to-use” fossil fuels that we depend on will be depleted some time in this century. (While coal reserves are larger and not expected to run out for 200 years at the current rate of extraction, once the other fossil fuels are depleted, the rate of coal extraction is expected to increase significantly, thereby accelerating the depletion of coal as well.) Fossil fuels are not considered renewable. They take too long—millions of year!—to re-form. It will ultimately be necessary to shift our dependence from non-renewable forms of energy to renewable forms such as solar (light energy), wind (motion energy), hydropower (gravitational and motion energy), and geothermal (heat and motion energy).
The shift to renewable forms of energy is also seen as a means to protect the environment. The air pollutants produced by fossil-fuel burning power plants and automobiles (including carbon dioxide, methane, sulfuric, and nitrous oxides) contribute to acid rain, global warming, and smog.
Global warming is considered a consequence of the greenhouse effect. When sunlight (light energy) travels through the glass of a greenhouse (or the windows of a car), it is transferred to heat energy—warming up the air and surfaces inside. Unlike light energy, heat energy does not move through glass easily. The glass traps heat energy inside, keeping plants warm enough to live in the winter. Greenhouse gases, such as carbon dioxide, methane, and water vapor, form a layer in the atmosphere that acts in a similar way—allowing sunlight to pass through, but trapping heat energy inside. This is good to a degree—Earth’s average temperature would be much colder without these gases. But problems arise if this layer is allowed to get thicker and thicker, trapping more and more heat, and causing Earth’s temperature to gradually rise. Even a slight rise in Earth’s temperature can have huge consequences.
Acid rain forms when oxides of nitrogen and sulfite—produced primarily by burning fossil fuels—combine with moisture in the atmosphere to make nitric and sulfuric acids. The result is precipitation with a pH level less than 5.6 that adversely affects the regions receiving it. The associated environmental damage over time can be great, including the destruction
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| ENERGY | TEaChER baCkGRouNd iNfoRmaTioN 2�4
of lake, stream, and forest habitats. Acid rain also damages man-made materials and structures, dissolving marble, limestone, and sandstone and corroding metals, paints, textiles, and ceramics.
Smog—the dark, hazy atmosphere that covers many major cities (particularly in the summer time)—is a combination of the words smoke and fog. Smog consists of over 100 chemicals, but the two most harmful components are ground-level ozone and fine airborne particles. Coal-fired power plant and automobile emissions account for much of the smog produced. Smog is a serious health concern, especially to children and the elderly—causing respiratory infections and chronic lung diseases such as asthma.
The methods used to extract fossil fuels are also problematic—disrupting native habitats and contaminating local waters with harmful run-off.
Energy sources that can be used instead of fossil fuels to generate electricity are called alternative energy sources. While many are considered less harmful to the environment, each nonetheless has a cost, environmental and otherwise. In the student reference book, the children are presented with the following table outlining the pros and cons of various energy sources. Developing a sense of the tradeoffs involved in using these energy sources should help foster critical thinking as today’s students prepare to address the energy needs of the future.
Energy Sources—Pros and ConsSource of Energy
Pros Cons
Fossil Fuels Abundant (though a non-renewable source); somewhat inexpensive; used to produce many products; technologies are already in place that rely on them (e.g., gasoline- powered cars, coal- burning power plants)
Produce air pollution associated with smog, acid rain, and global warming; require storage and transportation; drilling, mining, and exploration is expensive, destructive to local habitats, and often dangerous; can raise the temperature of local waters when water used to cool power plants is released into them
Energy Sources—Pros and ConsSource of Energy
Pros Cons
Solar Energy Unlimited supply; no air or water pollution; no fuel is needed
Depends on sunlight; a backup energy source is needed; solar panels are expensive; requires lots of land; some toxic chemicals are used to manufacture solar cells and batteries
Wind Energy No air or water pollution; no fuel is needed; not very expensive to build; land around wind farms can be used for other purposes
Requires steady winds; lots of land is needed; some wind farms cause noise pollution; some consider them unsightly; bats and migrating birds are often killed by spinning turbines and wires
Geothermal Energy
No pollution; power stations do not take up much room—less impact on the environment; no fuel is needed; once you’ve built a geothermal power station, the energy is almost free
Only a few places are suitable to build a geothermal power station; geothermal sites sometimes stop producing steam; at some sites, hazardous gases and minerals come up from underground that require safe disposal
Hydropower Abundant; no pollution; no fuel is needed; easily stored in reservoirs; somewhat inexpensive
Requires a water supply; the necessary dams and reservoirs disrupt native habitats; the best sites are already developed
Nuclear Energy No air pollution; fuel (uranium) is abundant and somewhat inexpensive; reactors need to be refueled only about once a year; the energy obtained from one pound of uranium is equal to the amount of energy in approximately three million pounds of coal
Costly to build; many safety regulations are involved; risk of the escape of dangerous radioactive material raises public concern; requires long-term (at least 10,000 years), safe disposal of dangerous radioactive waste; raises the temperature of local waters when water used to cool the reactors is released into them
2��
of lake, stream, and forest habitats. Acid rain also damages man-made materials and structures, dissolving marble, limestone, and sandstone and corroding metals, paints, textiles, and ceramics.
Smog—the dark, hazy atmosphere that covers many major cities (particularly in the summer time)—is a combination of the words smoke and fog. Smog consists of over 100 chemicals, but the two most harmful components are ground-level ozone and fine airborne particles. Coal-fired power plant and automobile emissions account for much of the smog produced. Smog is a serious health concern, especially to children and the elderly—causing respiratory infections and chronic lung diseases such as asthma.
The methods used to extract fossil fuels are also problematic—disrupting native habitats and contaminating local waters with harmful run-off.
Energy sources that can be used instead of fossil fuels to generate electricity are called alternative energy sources. While many are considered less harmful to the environment, each nonetheless has a cost, environmental and otherwise. In the student reference book, the children are presented with the following table outlining the pros and cons of various energy sources. Developing a sense of the tradeoffs involved in using these energy sources should help foster critical thinking as today’s students prepare to address the energy needs of the future.
Energy Sources—Pros and ConsSource of Energy
Pros Cons
Fossil Fuels Abundant (though a non-renewable source); somewhat inexpensive; used to produce many products; technologies are already in place that rely on them (e.g., gasoline- powered cars, coal- burning power plants)
Produce air pollution associated with smog, acid rain, and global warming; require storage and transportation; drilling, mining, and exploration is expensive, destructive to local habitats, and often dangerous; can raise the temperature of local waters when water used to cool power plants is released into them
Energy Sources—Pros and ConsSource of Energy
Pros Cons
Solar Energy Unlimited supply; no air or water pollution; no fuel is needed
Depends on sunlight; a backup energy source is needed; solar panels are expensive; requires lots of land; some toxic chemicals are used to manufacture solar cells and batteries
Wind Energy No air or water pollution; no fuel is needed; not very expensive to build; land around wind farms can be used for other purposes
Requires steady winds; lots of land is needed; some wind farms cause noise pollution; some consider them unsightly; bats and migrating birds are often killed by spinning turbines and wires
Geothermal Energy
No pollution; power stations do not take up much room—less impact on the environment; no fuel is needed; once you’ve built a geothermal power station, the energy is almost free
Only a few places are suitable to build a geothermal power station; geothermal sites sometimes stop producing steam; at some sites, hazardous gases and minerals come up from underground that require safe disposal
Hydropower Abundant; no pollution; no fuel is needed; easily stored in reservoirs; somewhat inexpensive
Requires a water supply; the necessary dams and reservoirs disrupt native habitats; the best sites are already developed
Nuclear Energy No air pollution; fuel (uranium) is abundant and somewhat inexpensive; reactors need to be refueled only about once a year; the energy obtained from one pound of uranium is equal to the amount of energy in approximately three million pounds of coal
Costly to build; many safety regulations are involved; risk of the escape of dangerous radioactive material raises public concern; requires long-term (at least 10,000 years), safe disposal of dangerous radioactive waste; raises the temperature of local waters when water used to cool the reactors is released into them
ENERGY | TEaChER baCkGRouNd iNfoRmaTioN |
2�6
Measuring EnergyAs stated in the beginning of this review, energy is a measurable property, not a substance. So how is energy measured? It turns out that energy is measured in many different ways using many different units. It helps to remember that each unit is simply a measure of energy and, as such, can be converted from one unit to another, just as energy itself is converted from one form to another.
Closely related to the measurement of energy is the measurement of temperature. Temperature is a measure of the average energy of motion of the atoms or molecules that make up a substance. It is important, however, to distinguish between average energy and total energy. Two objects could have the same temperature (meaning the average energy of their atoms and molecules is the same) but their total energy could be quite different. Total energy depends on the number of atoms and molecules present (the more atoms or molecules, the higher the total energy), as well as the type of atoms and molecules themselves. If, for example, you have two glasses of water in front of you, both registering the same temperature, and one has twice the volume as the other, the larger glass of water will have twice the total energy as the smaller one. This is why we are careful to say that “temperature is connected to the amount of heat energy in an object” but do not say that it is “a measure of the amount of heat energy in an object.”
There are three commonly used systems or scales for measuring temperature: Fahrenheit, Celsius, and Kelvin. Temperatures can be converted from one scale to another using the following equations:
• Fahrenheit to Celsius oC = (5/9) (oF - 32)
• Celsium to Fahrenheit oF = (9/5) oC + 32
• Celsius to Kelvin K = oC + 273
In the United States, a common unit of measure for comparing fuels is the British thermal unit (Btu). A Btu is the amount of energy required to raise the temperature of one pound of water one degree Fahrenheit at sea level. One Btu is roughly equivalent to the amount of heat given off when one match head is burned. The following are the Btu equivalents of some familiar fuels:
• 1 gallon of gasoline = 124,000 Btu
• 1 gallon of diesel fuel = 139,000 Btu
• 1 gallon of home heating oil = 139,000 Btu
• 1 cubic foot of natural gas = 1,026 Btu
• 1 gallon of propane = 91,000 Btu
• 1 barrel (42 gallons) of crude oil = 5,800,000 Btu
Scientists around the world measure energy in joules. A joule (designated with a capital “J”) is the basic unit of energy in the metric system—representing the amount of energy it takes to lift 100 grams (.1 kg) of anything one meter. One thousand joules is the approximate equivalent of one Btu.
The energy potential of food is measured in Calories. A food Calorie (noted with a capital “C”) is actually a kilocalorie—equivalent to 1000 calories (small “c”). A calorie is the quantity of heat required to raise the temperature of one gram of water one degree Celsius at a pressure of one atmosphere (an arbitrary representative value for air pressure at sea level). One calorie is equivalent to 4.19 joules. Since one joule represents the amount of energy it takes to lift 100 grams of anything one meter, you can see that to “burn” one (little) calorie, you’d have to lift a 100 gram mass up and down a distance of one meter a little over four times. To burn one food Calorie, you’d have to do it about 4000 times!
Electrical power is measured in watts. Watts indicate the rate at which electricity is used. The amount of energy used by household appliances is usually described in kilowatt-hours. One kilowatt-hour (kWh), for which you are charged about $.10 - $.20, is equivalent to 1000 watts sustained for one hour. Energy-efficient refrigerators use about 1.4 kilowatt-hours per day, and about 500 kilowatt-hours per year. One kilowatt-hour of electricity is equivalent to 3,412 Btu.
“Energy” Impact StatementClearly “energy” is an immense topic. Every discipline of science (biology, geology, ecology, physics, medicine, chemistry, meteorology, astronomy, and so on) seeks to understand energy and its impact—on life, molecular behavior, the movement of Earth’s plates, weather patterns, chemical behavior, the lives of stars, and more.
At work (remember that scientists define energy in terms of its ability to perform work), doctors, engineers, scientists, gardeners, nutritionists, politicians, construction workers, and athletes rely on energy. At play, budding soccer stars, musicians, gazers of fireworks, and riders of swings have fun thanks to energy’s ability to make things happen.
Energy is inescapable! We hope that this unit opens students’ eyes to the energy all around them, helping them recognize the enormous role that energy plays in their lives and their world, and providing them with the foundation to further explore and understand the significance of energy as they progress through school, work, and life.
| ENERGY | TEaChER baCkGRouNd iNfoRmaTioN
2��
Measuring EnergyAs stated in the beginning of this review, energy is a measurable property, not a substance. So how is energy measured? It turns out that energy is measured in many different ways using many different units. It helps to remember that each unit is simply a measure of energy and, as such, can be converted from one unit to another, just as energy itself is converted from one form to another.
Closely related to the measurement of energy is the measurement of temperature. Temperature is a measure of the average energy of motion of the atoms or molecules that make up a substance. It is important, however, to distinguish between average energy and total energy. Two objects could have the same temperature (meaning the average energy of their atoms and molecules is the same) but their total energy could be quite different. Total energy depends on the number of atoms and molecules present (the more atoms or molecules, the higher the total energy), as well as the type of atoms and molecules themselves. If, for example, you have two glasses of water in front of you, both registering the same temperature, and one has twice the volume as the other, the larger glass of water will have twice the total energy as the smaller one. This is why we are careful to say that “temperature is connected to the amount of heat energy in an object” but do not say that it is “a measure of the amount of heat energy in an object.”
There are three commonly used systems or scales for measuring temperature: Fahrenheit, Celsius, and Kelvin. Temperatures can be converted from one scale to another using the following equations:
• Fahrenheit to Celsius oC = (5/9) (oF - 32)
• Celsium to Fahrenheit oF = (9/5) oC + 32
• Celsius to Kelvin K = oC + 273
In the United States, a common unit of measure for comparing fuels is the British thermal unit (Btu). A Btu is the amount of energy required to raise the temperature of one pound of water one degree Fahrenheit at sea level. One Btu is roughly equivalent to the amount of heat given off when one match head is burned. The following are the Btu equivalents of some familiar fuels:
• 1 gallon of gasoline = 124,000 Btu
• 1 gallon of diesel fuel = 139,000 Btu
• 1 gallon of home heating oil = 139,000 Btu
• 1 cubic foot of natural gas = 1,026 Btu
• 1 gallon of propane = 91,000 Btu
• 1 barrel (42 gallons) of crude oil = 5,800,000 Btu
Scientists around the world measure energy in joules. A joule (designated with a capital “J”) is the basic unit of energy in the metric system—representing the amount of energy it takes to lift 100 grams (.1 kg) of anything one meter. One thousand joules is the approximate equivalent of one Btu.
The energy potential of food is measured in Calories. A food Calorie (noted with a capital “C”) is actually a kilocalorie—equivalent to 1000 calories (small “c”). A calorie is the quantity of heat required to raise the temperature of one gram of water one degree Celsius at a pressure of one atmosphere (an arbitrary representative value for air pressure at sea level). One calorie is equivalent to 4.19 joules. Since one joule represents the amount of energy it takes to lift 100 grams of anything one meter, you can see that to “burn” one (little) calorie, you’d have to lift a 100 gram mass up and down a distance of one meter a little over four times. To burn one food Calorie, you’d have to do it about 4000 times!
Electrical power is measured in watts. Watts indicate the rate at which electricity is used. The amount of energy used by household appliances is usually described in kilowatt-hours. One kilowatt-hour (kWh), for which you are charged about $.10 - $.20, is equivalent to 1000 watts sustained for one hour. Energy-efficient refrigerators use about 1.4 kilowatt-hours per day, and about 500 kilowatt-hours per year. One kilowatt-hour of electricity is equivalent to 3,412 Btu.
“Energy” Impact StatementClearly “energy” is an immense topic. Every discipline of science (biology, geology, ecology, physics, medicine, chemistry, meteorology, astronomy, and so on) seeks to understand energy and its impact—on life, molecular behavior, the movement of Earth’s plates, weather patterns, chemical behavior, the lives of stars, and more.
At work (remember that scientists define energy in terms of its ability to perform work), doctors, engineers, scientists, gardeners, nutritionists, politicians, construction workers, and athletes rely on energy. At play, budding soccer stars, musicians, gazers of fireworks, and riders of swings have fun thanks to energy’s ability to make things happen.
Energy is inescapable! We hope that this unit opens students’ eyes to the energy all around them, helping them recognize the enormous role that energy plays in their lives and their world, and providing them with the foundation to further explore and understand the significance of energy as they progress through school, work, and life.
ENERGY | TEaChER baCkGRouNd iNfoRmaTioN |
| ENERGY | sTaNdaRds 2��
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BA
. Sci
ence
as
Inqu
iry
Abi
litie
s N
eces
sary
to d
o Sc
ient
ific
Inqu
iry
Ask
a q
uest
ion
abou
t obj
ects
, org
anis
ms,
and
even
ts in
the
envi
ronm
ent.
(Gra
des
K-4)
OO
OO
OO
OO
O
Plan
and
con
duct
a s
impl
e in
vest
igat
ion.
(G
rade
s K-
4)F
Com
mun
icat
e in
vest
igat
ions
and
exp
lana
tions
. (G
rade
s K-
4)O
OO
OO
OO
Use
app
ropr
iate
tool
s an
d te
chni
ques
to g
athe
r, an
alyz
e, a
nd in
terp
ret d
ata.
OO
F
Dev
elop
des
crip
tions
, exp
lana
tions
, pr
edic
tions
, and
mod
els
usin
g ev
iden
ce.
OO
OO
Thin
k cr
itica
lly a
nd lo
gica
lly to
mak
e th
e re
latio
nshi
ps b
etw
een
evid
ence
and
ex
plan
atio
ns.
OO
OO
OO
Und
erst
andi
ngs
Abo
ut S
cien
tific
Inqu
iry
Scie
ntifi
c in
vest
igat
ions
invo
lve
aski
ng a
nd
answ
erin
g a
ques
tion
and
com
parin
g th
e an
swer
with
wha
t sci
entis
ts a
lread
y kn
ow
abou
t the
wor
ld. (
Gra
des
K-4)
FO
Scie
ntis
ts u
se d
iffer
ent k
inds
of i
nves
tigat
ions
de
pend
ing
on th
e qu
estio
ns th
ey a
re tr
ying
to
ans
wer
. Typ
es o
f inv
estig
atio
ns in
clud
e de
scrib
ing
obje
cts,
even
ts, a
nd o
rgan
ism
s;
clas
sify
ing
them
; and
doi
ng a
fair
test
(e
xper
imen
ting)
. (G
rade
s K-
4)
F
Scie
ntis
ts m
ake
the
resu
lts o
f the
ir in
vest
igat
ions
pub
lic; t
hey
desc
ribe
the
inve
stig
atio
ns in
way
s th
at e
nabl
e ot
hers
to
repe
at th
e in
vest
igat
ions
. (G
rade
s K-
4)
OO
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
Stan
dard
s (P
age
1 of
8)
ST
An
DA
RD
S A
nD
B
En
CH
MA
RK
S
2��ENERGY | sTaNdaRds |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BSc
ient
ists
revi
ew a
nd a
sk q
uest
ions
abo
ut th
e re
sults
of o
ther
sci
entis
ts’ w
ork.
(Gra
des
K-4)
OO
OO
Diff
eren
t kin
ds o
f que
stio
ns s
ugge
st
diffe
rent
kin
ds o
f sci
entif
ic in
vest
igat
ions
. So
me
inve
stig
atio
ns in
volv
e ob
serv
ing
and
desc
ribin
g ob
ject
s, or
gani
sms,
or e
vent
s; s
ome
invo
lve
colle
ctin
g sp
ecim
ens;
som
e in
volv
e ex
perim
ents
; som
e in
volv
e se
ekin
g m
ore
info
rmat
ion;
som
e in
volv
e di
scov
ery
of n
ew
obje
cts
and
phen
omen
a; a
nd s
ome
invo
lve
mak
ing
mod
els.
OO
OO
OO
OO
OO
OO
Curr
ent s
cien
tific
kno
wle
dge
and
unde
rsta
ndin
g gu
ide
scie
ntifi
c in
vest
igat
ions
. D
iffer
ent s
cien
tific
dom
ains
em
ploy
diff
eren
t m
etho
ds, c
ore
theo
ries,
and
stan
dard
s to
adv
ance
sci
entif
ic k
now
ledg
e an
d un
ders
tand
ing.
O
Tech
nolo
gy u
sed
to g
athe
r dat
a en
hanc
es
accu
racy
and
allo
ws
scie
ntis
ts to
ana
lyze
and
qu
antif
y re
sults
of i
nves
tigat
ions
.O
Scie
ntifi
c ex
plan
atio
ns e
mph
asiz
e ev
iden
ce,
have
logi
cally
con
sist
ent a
rgum
ents
, and
use
sc
ient
ific
prin
cipl
es, m
odel
s, an
d th
eorie
s. Th
e sc
ient
ific
com
mun
ity a
ccep
ts a
nd u
ses
such
ex
plan
atio
ns u
ntil
disp
lace
d by
bet
ter s
cien
tific
on
es. W
hen
such
dis
plac
emen
t occ
urs,
scie
nce
adva
nces
.
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
Stan
dard
s (P
age
2 of
8)
ST
An
DA
RD
S A
nD
B
En
CH
MA
RK
S
| ENERGY | sTaNdaRds 260
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BSc
ienc
e ad
vanc
es th
roug
h le
gitim
ate
skep
ticis
m. A
skin
g qu
estio
ns a
nd q
uery
ing
othe
r sci
entis
ts’ e
xpla
natio
ns is
par
t of s
cien
tific
in
quiry
. Sci
entis
ts e
valu
ate
the
expl
anat
ions
pr
opos
ed b
y ot
her s
cien
tists
by
exam
inin
g ev
iden
ce, c
ompa
ring
evid
ence
, ide
ntify
ing
faul
ty re
ason
ing,
poi
ntin
g ou
t sta
tem
ents
th
at g
o be
yond
the
evid
ence
, and
sug
gest
ing
alte
rnat
ive
expl
anat
ions
for t
he s
ame
obse
rvat
ions
.
O
Scie
ntifi
c in
vest
igat
ions
som
etim
es re
sult
in n
ew id
eas
and
phen
omen
a fo
r stu
dy,
gene
rate
new
met
hods
or p
roce
dure
s fo
r an
inve
stig
atio
n, o
r dev
elop
new
tech
nolo
gies
to
impr
ove
the
colle
ctio
n of
dat
a. A
ll of
thes
e re
sults
can
lead
to n
ew in
vest
igat
ions
.
O
B. P
hysi
cal S
cien
ce
Tran
sfer
of E
nerg
y
Ener
gy is
a p
rope
rty
of m
any
subs
tanc
es
and
is a
ssoc
iate
d w
ith h
eat,
light
, ele
ctric
ity,
mec
hani
cal m
otio
n, s
ound
, nuc
lei,
and
the
natu
re o
f a c
hem
ical
. Ene
rgy
is tr
ansf
erre
d in
m
any
way
s.
FF
FF
OO
OO
FF
Hea
t mov
es in
pre
dict
able
way
s, flo
win
g fr
om
war
mer
obj
ects
to c
oole
r one
s, un
til b
oth
reac
h th
e sa
me
tem
pera
ture
.F
FF
O
Elec
tric
al c
ircui
ts p
rovi
de a
mea
ns o
f tr
ansf
errin
g el
ectr
ical
ene
rgy
whe
n he
at, l
ight
, so
und,
and
che
mic
al c
hang
es a
re p
rodu
ced.
EO
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
Stan
dard
s (P
age
3 of
8)
261ENERGY | sTaNdaRds |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BIn
mos
t che
mic
al a
nd n
ucle
ar re
actio
ns, e
nerg
y is
tran
sfer
red
into
or o
ut o
f a s
yste
m. H
eat,
light
, mec
hani
cal m
otio
n, o
r ele
ctric
ity m
ight
al
l be
invo
lved
in s
uch
tran
sfer
s.
OO
The
sun
is a
maj
or s
ourc
e of
ene
rgy
for c
hang
es
on th
e ea
rth’
s su
rfac
e. T
he s
un lo
ses
ener
gy
by e
mitt
ing
light
. A ti
ny fr
actio
n of
that
ligh
t re
ache
s th
e ea
rth,
tran
sfer
ring
ener
gy fr
om th
e su
n to
the
eart
h. T
he s
un’s
ener
gy a
rriv
es a
s lig
ht w
ith a
rang
e of
wav
elen
gths
, con
sist
ing
of
visi
ble
light
, inf
rare
d, a
nd u
ltrav
iole
t rad
iatio
n.
O
C. L
ife S
cien
ce
Popu
latio
ns a
nd E
cosy
stem
s
For e
cosy
stem
s, th
e m
ajor
sou
rce
of e
nerg
y is
sun
light
. Ene
rgy
ente
ring
ecos
yste
ms
as
sunl
ight
is tr
ansf
erre
d by
pro
duce
rs in
to
chem
ical
ene
rgy
thro
ugh
phot
osyn
thes
is. T
hat
ener
gy th
en p
asse
s fr
om o
rgan
ism
to o
rgan
ism
in
food
web
s.
O
D. E
arth
and
Spa
ce S
cien
ce
Eart
h in
the
Sola
r Sys
tem
The
sun
is th
e m
ajor
sou
rce
of e
nerg
y fo
r ph
enom
ena
on th
e ea
rth’
s su
rfac
e, s
uch
as
grow
th o
f pla
nts,
win
ds, o
cean
cur
rent
s, an
d th
e w
ater
cyc
le. S
easo
ns re
sult
from
var
iatio
ns
in th
e am
ount
of t
he s
un’s
ener
gy h
ittin
g th
e su
rfac
e, d
ue to
the
tilt o
f the
ear
th’s
rota
tion
on
its a
xis
and
the
leng
th o
f the
day
.
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
Stan
dard
s (P
age
4 of
8)
| ENERGY | sTaNdaRds 262
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BE.
Sci
ence
and
Tec
hnol
ogy
Abi
litie
s of
Tec
hnol
ogic
al D
esig
n
Des
ign
a so
lutio
n or
pro
duct
.F
Impl
emen
t a p
ropo
sed
desi
gn.
O
Und
erst
andi
ngs
abou
t Sci
ence
and
Tec
hnol
ogy
Peop
le h
ave
alw
ays
had
ques
tions
abo
ut
thei
r wor
ld. S
cien
ce is
one
way
of a
nsw
erin
g qu
estio
ns a
nd e
xpla
inin
g th
e na
tura
l wor
ld.
(Gra
des
K-4)
OO
Scie
ntis
ts a
nd e
ngin
eers
oft
en w
ork
in te
ams
with
diff
eren
t ind
ivid
uals
doi
ng d
iffer
ent
thin
gs th
at c
ontr
ibut
e to
the
resu
lts. T
his
unde
rsta
ndin
g fo
cuse
s pr
imar
ily o
n te
ams
wor
king
toge
ther
and
sec
onda
rily,
on
the
com
bina
tion
of s
cien
tist a
nd e
ngin
eer t
eam
s. (G
rade
s K-
4)
O
Man
y di
ffere
nt p
eopl
e in
diff
eren
t cul
ture
s ha
ve
mad
e an
d co
ntin
ue to
mak
e co
ntrib
utio
ns to
sc
ienc
e an
d te
chno
logy
. O
Scie
nce
and
tech
nolo
gy a
re re
cipr
ocal
. Sc
ienc
e he
lps
driv
e te
chno
logy
, as
it ad
dres
ses
ques
tions
that
dem
and
mor
e so
phis
ticat
ed
inst
rum
ents
and
pro
vide
s pr
inci
ples
for b
ette
r in
stru
men
tatio
n an
d te
chni
que.
Tec
hnol
ogy
is e
ssen
tial t
o sc
ienc
e, b
ecau
se it
pro
vide
s in
stru
men
ts a
nd te
chni
ques
that
ena
ble
obse
rvat
ions
of o
bjec
ts a
nd p
heno
men
a th
at
are
othe
rwis
e un
obse
rvab
le d
ue to
fact
ors
such
as
quan
tity,
dis
tanc
e, lo
catio
n, s
ize,
and
sp
eed.
Tec
hnol
ogy
also
pro
vide
s to
ols
for
inve
stig
atio
ns, i
nqui
ry, a
nd a
naly
sis.
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
Stan
dard
s (P
age
5 of
8)
263ENERGY | sTaNdaRds |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BPe
rfec
tly d
esig
ned
solu
tions
do
not e
xist
. All
tech
nolo
gica
l sol
utio
ns h
ave
trad
e-of
fs, s
uch
as s
afet
y, c
ost,
effic
ienc
y, a
nd a
ppea
ranc
e.
Engi
neer
s of
ten
build
in b
ack-
up s
yste
ms
to
prov
ide
safe
ty. R
isk
is p
art o
f liv
ing
in a
hig
hly
tech
nolo
gica
l wor
ld. R
educ
ing
risk
ofte
n re
sults
in
new
tech
nolo
gy.
O
Tech
nolo
gica
l des
igns
hav
e co
nstr
aint
s. So
me
cons
trai
nts
are
unav
oida
ble,
for e
xam
ple,
pr
oper
ties
of m
ater
ials
, or e
ffect
s of
wea
ther
an
d fr
ictio
n; o
ther
con
stra
ints
lim
it ch
oice
s in
the
desi
gn, f
or e
xam
ple,
env
ironm
enta
l pr
otec
tion,
hum
an s
afet
y, a
nd a
esth
etic
s.
O
F. S
cien
ce in
Per
sona
l and
Soc
ial P
ersp
ecti
ves
Pers
onal
Hea
lth
Food
pro
vide
s en
ergy
and
nut
rient
s fo
r gro
wth
an
d de
velo
pmen
t. N
utrit
ion
requ
irem
ents
var
y w
ith b
ody
wei
ght,
age,
sex
, act
ivity
, and
bod
y fu
nctio
ning
.
OO
Nat
ural
env
ironm
ents
may
con
tain
sub
stan
ces
(for e
xam
ple,
rado
n an
d le
ad) t
hat a
re h
arm
ful
to h
uman
bei
ngs.
Mai
ntai
ning
env
ironm
enta
l he
alth
invo
lves
est
ablis
hing
or m
onito
ring
qual
ity s
tand
ards
rela
ted
to u
se o
f soi
l, w
ater
, an
d ai
r.
O
Scie
nce
and
Tech
nolo
gy in
Soc
iety
Scie
nce
influ
ence
s soc
iety
thro
ugh
its k
now
ledg
e an
d w
orld
vie
w. S
cien
tific
kno
wle
dge
and
the
proc
edur
es u
sed
by sc
ient
ists i
nflu
ence
the
way
man
y in
divi
dual
s in
soci
ety
thin
k ab
out
them
selv
es, o
ther
s, an
d th
e en
viro
nmen
t. Th
e ef
fect
of s
cien
ce o
n so
ciet
y is
neith
er e
ntire
ly
bene
ficia
l nor
ent
irely
det
rimen
tal.
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
Stan
dard
s (P
age
6 of
8)
| ENERGY | sTaNdaRds 264
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BSc
ienc
e an
d te
chno
logy
hav
e ad
vanc
ed
thro
ugh
cont
ribut
ions
of m
any
diffe
rent
pe
ople
, in
diffe
rent
cul
ture
s, at
diff
eren
t tim
es in
his
tory
. Sci
ence
and
tech
nolo
gy h
ave
cont
ribut
ed e
norm
ousl
y to
eco
nom
ic g
row
th
and
prod
uctiv
ity a
mon
g so
ciet
ies
and
grou
ps
with
in s
ocie
ties.
F
G. H
isto
ry a
nd N
atur
e of
Sci
ence
Scie
nce
as a
Hum
an E
ndea
vor
Wom
en a
nd m
en o
f var
ious
soc
ial a
nd e
thni
c ba
ckgr
ound
s-an
d w
ith d
iver
se in
tere
sts,
tale
nts,
qual
ities
, and
mot
ivat
ions
-eng
age
in th
e ac
tiviti
es o
f sci
ence
, eng
inee
ring,
and
rela
ted
field
s su
ch a
s th
e he
alth
pro
fess
ions
. Som
e sc
ient
ists
wor
k in
team
s, an
d so
me
wor
k al
one,
bu
t all
com
mun
icat
e ex
tens
ivel
y w
ith o
ther
s.
O
Scie
nce
requ
ires
diffe
rent
abi
litie
s, de
pend
ing
on s
uch
fact
ors
as th
e fie
ld o
f stu
dy a
nd ty
pe
of in
quiry
. Sci
ence
is v
ery
muc
h a
hum
an
ende
avor
, and
the
wor
k of
sci
ence
relie
s on
ba
sic
hum
an q
ualit
ies,
such
as
reas
onin
g,
insi
ght,
ener
gy, s
kill,
and
cre
ativ
ity-a
s w
ell a
s on
sci
entif
ic h
abits
of m
ind,
suc
h as
inte
llect
ual
hone
sty,
tole
ranc
e of
am
bigu
ity, s
kept
icis
m,
and
open
ness
to n
ew id
eas.
OO
His
tory
of S
cien
ce
Man
y in
divi
dual
s ha
ve c
ontr
ibut
ed to
the
trad
ition
s of
sci
ence
. Stu
dyin
g so
me
of th
ese
indi
vidu
als
prov
ides
furt
her u
nder
stan
ding
of
scie
ntifi
c in
quiry
, sci
ence
as
a hu
man
end
eavo
r, th
e na
ture
of s
cien
ce, a
nd th
e re
latio
nshi
ps
betw
een
scie
nce
and
soci
ety.
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
Stan
dard
s (P
age
7 of
8)
26�ENERGY | sTaNdaRds |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BSc
ienc
e an
d te
chno
logy
hav
e ad
vanc
ed
thro
ugh
cont
ribut
ions
of m
any
diffe
rent
pe
ople
, in
diffe
rent
cul
ture
s, at
diff
eren
t tim
es in
his
tory
. Sci
ence
and
tech
nolo
gy h
ave
cont
ribut
ed e
norm
ousl
y to
eco
nom
ic g
row
th
and
prod
uctiv
ity a
mon
g so
ciet
ies
and
grou
ps
with
in s
ocie
ties.
F
G. H
isto
ry a
nd N
atur
e of
Sci
ence
Scie
nce
as a
Hum
an E
ndea
vor
Wom
en a
nd m
en o
f var
ious
soc
ial a
nd e
thni
c ba
ckgr
ound
s-an
d w
ith d
iver
se in
tere
sts,
tale
nts,
qual
ities
, and
mot
ivat
ions
-eng
age
in th
e ac
tiviti
es o
f sci
ence
, eng
inee
ring,
and
rela
ted
field
s su
ch a
s th
e he
alth
pro
fess
ions
. Som
e sc
ient
ists
wor
k in
team
s, an
d so
me
wor
k al
one,
bu
t all
com
mun
icat
e ex
tens
ivel
y w
ith o
ther
s.
O
Scie
nce
requ
ires
diffe
rent
abi
litie
s, de
pend
ing
on s
uch
fact
ors
as th
e fie
ld o
f stu
dy a
nd ty
pe
of in
quiry
. Sci
ence
is v
ery
muc
h a
hum
an
ende
avor
, and
the
wor
k of
sci
ence
relie
s on
ba
sic
hum
an q
ualit
ies,
such
as
reas
onin
g,
insi
ght,
ener
gy, s
kill,
and
cre
ativ
ity-a
s w
ell a
s on
sci
entif
ic h
abits
of m
ind,
suc
h as
inte
llect
ual
hone
sty,
tole
ranc
e of
am
bigu
ity, s
kept
icis
m,
and
open
ness
to n
ew id
eas.
OO
His
tory
of S
cien
ce
Man
y in
divi
dual
s ha
ve c
ontr
ibut
ed to
the
trad
ition
s of
sci
ence
. Stu
dyin
g so
me
of th
ese
indi
vidu
als
prov
ides
furt
her u
nder
stan
ding
of
scie
ntifi
c in
quiry
, sci
ence
as
a hu
man
end
eavo
r, th
e na
ture
of s
cien
ce, a
nd th
e re
latio
nshi
ps
betw
een
scie
nce
and
soci
ety.
O
Nat
iona
l Res
earc
h Co
unci
l. N
atio
nal S
cien
ce E
duca
tion
Stan
dard
s. W
ashi
ngto
n, D
.C.:
Nat
iona
l Aca
dem
y Pr
ess,
1996
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
STA
ND
ARD
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BIn
his
toric
al p
ersp
ectiv
e, s
cien
ce h
as b
een
prac
ticed
by
diffe
rent
indi
vidu
als
in d
iffer
ent
cultu
res.
In lo
okin
g at
the
hist
ory
of m
any
peop
les,
one
finds
that
sci
entis
ts a
nd e
ngin
eers
of
hig
h ac
hiev
emen
t are
con
side
red
to b
e am
ong
the
mos
t val
ued
cont
ribut
ors
to th
eir
cultu
re.
O
Trac
ing
the
hist
ory
of s
cien
ce c
an s
how
how
di
fficu
lt it
was
for s
cien
tific
inno
vato
rs to
bre
ak
thro
ugh
the
acce
pted
idea
s of
thei
r tim
e to
re
ach
the
conc
lusi
ons
that
we
curr
ently
take
for
gran
ted.
O
Uni
fyin
g Co
ncep
ts a
nd P
roce
sses
Evid
ence
, mod
els,
and
expl
anat
ion
OO
OO
ON
atio
nal R
esea
rch
Coun
cil.
Nat
iona
l Sci
ence
Edu
catio
n St
anda
rds.
Was
hing
ton,
D.C
.: N
atio
nal A
cade
my
Pres
s, 19
96
Stan
dard
s (P
age
8 of
8)
| ENERGY | bENChmaRks 266
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
B1.
The
Nat
ure
of S
cien
ce
A. T
he S
cien
tific
Wor
ld V
iew
Resu
lts o
f sim
ilar s
cien
tific
inve
stig
atio
ns
seld
om tu
rn o
ut e
xact
ly th
e sa
me.
So
met
imes
this
is b
ecau
se o
f une
xpec
ted
diffe
renc
es in
the
thin
gs b
eing
inve
stig
ated
, so
met
imes
bec
ause
of u
nrea
lized
diff
eren
ces
in th
e m
etho
ds u
sed
or in
the
circ
umst
ance
s in
whi
ch th
e in
vest
igat
ion
is c
arrie
d ou
t, an
d so
met
imes
just
bec
ause
of u
ncer
tain
ties
in o
bser
vatio
ns. I
t is
not a
lway
s ea
sy to
tell
whi
ch.
OO
O
B. S
cien
tific
Inqu
iry
Des
crib
ing
thin
gs a
s ac
cura
tely
as
poss
ible
is
impo
rtan
t in
scie
nce
beca
use
it en
able
s pe
ople
to c
ompa
re th
eir o
bser
vatio
ns w
ith
thos
e of
oth
ers.
(Gra
des
K-2)
OO
OO
F
Scie
ntifi
c in
vest
igat
ions
may
take
man
y di
ffere
nt fo
rms,
incl
udin
g ob
serv
ing
wha
t thi
ngs
are
like
or w
hat i
s ha
ppen
ing
som
ewhe
re, c
olle
ctin
g sp
ecim
ens
for a
naly
sis,
and
doin
g ex
perim
ents
. In
vest
igat
ions
can
focu
s on
phy
sica
l, bi
olog
ical
, and
soc
ial q
uest
ions
.
OO
OO
OO
OO
OO
OO
Resu
lts o
f sci
entif
ic in
vest
igat
ions
are
se
ldom
exa
ctly
the
sam
e, b
ut if
the
diffe
renc
es a
re la
rge,
it is
impo
rtan
t to
try
to fi
gure
out
why
. One
reas
on fo
r fol
low
ing
dire
ctio
ns c
aref
ully
and
for k
eepi
ng re
cord
s of
one
’s w
ork
is to
pro
vide
info
rmat
ion
on
wha
t mig
ht h
ave
caus
ed th
e di
ffere
nces
.
OO
OO
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
1 o
f 10)
26�ENERGY | bENChmaRks |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BSc
ient
ists
’ exp
lana
tions
abo
ut w
hat
happ
ens
in th
e w
orld
com
e pa
rtly
from
w
hat t
hey
obse
rve,
par
tly fr
om w
hat
they
thin
k. S
omet
imes
sci
entis
ts h
ave
diffe
rent
exp
lana
tions
for t
he s
ame
set o
f ob
serv
atio
ns. T
hat u
sual
ly le
ads
to th
eir
mak
ing
mor
e ob
serv
atio
ns to
reso
lve
the
diffe
renc
es.
FO
OO
OO
If m
ore
than
one
var
iabl
e ch
ange
s at
the
sam
e tim
e in
an
expe
rimen
t, th
e ou
tcom
e of
the
expe
rimen
t may
not
be
clea
rly
attr
ibut
able
to a
ny o
ne o
f the
var
iabl
es.
(Gra
des
6-8)
OO
F
C. T
he S
cien
tific
Ent
erpr
ise
Scie
nce
is a
n ad
vent
ure
that
peo
ple
ever
ywhe
re c
an ta
ke p
art i
n, a
s th
ey h
ave
for
man
y ce
ntur
ies.
O
Clea
r com
mun
icat
ion
is a
n es
sent
ial p
art o
f do
ing
scie
nce.
It e
nabl
es s
cien
tists
to in
form
ot
hers
abo
ut th
eir w
ork,
exp
ose
thei
r ide
as
to c
ritic
ism
by
othe
r sci
entis
ts, a
nd s
tay
info
rmed
abo
ut s
cien
tific
dis
cove
ries
arou
nd
the
wor
ld.
OO
OO
OO
OO
OF
OO
O
Doi
ng s
cien
ce in
volv
es m
any
diffe
rent
kin
ds
of w
ork
and
enga
ges
men
and
wom
en o
f all
ages
and
bac
kgro
unds
.O
2. T
he N
atur
e of
Mat
hem
atic
s
A. P
atte
rns
and
Rela
tions
hips
Mat
hem
atic
al id
eas
can
be re
pres
ente
d co
ncre
tely
, gra
phic
ally
, and
sym
bolic
ally
.O
OO
O
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
2 o
f 10)
| ENERGY | bENChmaRks 26�
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
B3.
The
Nat
ure
of T
echn
olog
y
A. T
echn
olog
y an
d Sc
ienc
e
Thro
ugho
ut a
ll of
his
tory
, peo
ple
ever
ywhe
re h
ave
inve
nted
and
use
d to
ols.
Mos
t too
ls o
f tod
ay a
re d
iffer
ent f
rom
thos
e of
the
past
but
man
y ar
e m
odifi
catio
ns o
f ve
ry a
ncie
nt to
ols.
O
Mea
surin
g in
stru
men
ts c
an b
e us
ed to
ga
ther
acc
urat
e in
form
atio
n fo
r mak
ing
scie
ntifi
c co
mpa
rison
s of
obj
ects
and
eve
nts
and
for d
esig
ning
and
con
stru
ctin
g th
ings
th
at w
ill w
ork
prop
erly
.
OO
FO
Tech
nolo
gy e
xten
ds th
e ab
ility
of p
eopl
e to
cha
nge
the
wor
ld: t
o cu
t, sh
ape,
or p
ut
toge
ther
mat
eria
ls; t
o m
ove
thin
gs fr
om
one
plac
e to
ano
ther
; and
to re
ach
fart
her
with
thei
r han
ds, v
oice
s, se
nses
, and
min
ds.
The
chan
ges
may
be
for s
urvi
val n
eeds
su
ch a
s fo
od, s
helte
r, an
d de
fens
e, fo
r co
mm
unic
atio
n an
d tr
ansp
orta
tion,
or t
o ga
in k
now
ledg
e an
d ex
pres
s id
eas.
O
B. D
esig
n an
d Sy
stem
s
Ther
e is
no
perf
ect d
esig
n. D
esig
ns th
at a
re
best
in o
ne re
spec
t (sa
fety
or e
ase
of u
se,
for e
xam
ple)
may
be
infe
rior i
n ot
her w
ays
(cos
t or a
ppea
ranc
e). U
sual
ly s
ome
feat
ures
m
ust b
e sa
crifi
ced
to g
et o
ther
s. H
ow s
uch
trad
e-of
fs a
re re
ceiv
ed d
epen
ds u
pon
whi
ch
feat
ures
are
em
phas
ized
and
whi
ch a
re
dow
npla
yed.
OO
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
3 o
f 10)
26�ENERGY | bENChmaRks |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BEv
en a
goo
d de
sign
may
fail.
Som
etim
es
step
s ca
n be
take
n ah
ead
of ti
me
to re
duce
th
e lik
elih
ood
of fa
ilure
, but
it c
anno
t be
entir
ely
elim
inat
ed.
O
C. Is
sues
in T
echn
olog
y
Tech
nolo
gy h
as b
een
part
of l
ife o
n th
e ea
rth
sinc
e th
e ad
vent
of t
he h
uman
sp
ecie
s. L
ike
lang
uage
, ritu
al, c
omm
erce
, an
d th
e ar
ts, t
echn
olog
y is
an
intr
insi
c pa
rt o
f hum
an c
ultu
re, a
nd it
bot
h sh
apes
so
ciet
y an
d is
sha
ped
by it
. The
tech
nolo
gy
avai
labl
e to
peo
ple
grea
tly in
fluen
ces
wha
t th
eir l
ives
are
like
.
O
Any
inve
ntio
n is
like
ly to
lead
to o
ther
in
vent
ions
. Onc
e an
inve
ntio
n ex
ists
, peo
ple
are
likel
y to
thin
k up
way
s of
usi
ng it
that
w
ere
neve
r im
agin
ed a
t firs
t.
O
Tran
spor
tatio
n, c
omm
unic
atio
ns, n
utrit
ion,
sa
nita
tion,
hea
lth c
are,
ent
erta
inm
ent,
and
othe
r tec
hnol
ogie
s gi
ve la
rge
num
bers
of
peop
le to
day
the
good
s an
d se
rvic
es th
at
once
wer
e lu
xurie
s en
joye
d on
ly b
y th
e w
ealth
y. T
hese
ben
efits
are
not
equ
ally
av
aila
ble
to e
very
one.
O
Tech
nolo
gies
oft
en h
ave
draw
back
s as
wel
l as
ben
efits
. A te
chno
logy
that
hel
ps s
ome
peop
le o
r org
anis
ms
may
hur
t oth
ers-
eith
er d
elib
erat
ely
(as
wea
pons
can
) or
inad
vert
ently
(as
pest
icid
es c
an).
Whe
n ha
rm
occu
rs o
r see
ms
likel
y, c
hoic
es h
ave
to b
e m
ade
or n
ew s
olut
ions
foun
d.
O
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
4 o
f 10)
| ENERGY | bENChmaRks 2�0
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
B4.
The
Phy
sica
l Set
ting
B. T
he E
arth
Thin
gs o
n or
nea
r the
ear
th a
re p
ulle
d to
war
d it
by th
e ea
rth’
s gr
avity
.O
O
Whe
n liq
uid
wat
er d
isap
pear
s, it
turn
s in
to
a ga
s (v
apor
) in
the
air a
nd c
an re
appe
ar a
s a
liqui
d w
hen
cool
ed, o
r as
a so
lid if
coo
led
belo
w th
e fr
eezi
ng p
oint
of w
ater
. Clo
uds
and
fog
are
mad
e of
tiny
dro
plet
s of
wat
er.
O
Air
is a
sub
stan
ce th
at s
urro
unds
us,
take
s up
spa
ce, a
nd w
hose
mov
emen
t we
feel
as
win
d.O
E. E
nerg
y Tr
ansf
orm
atio
n
Thin
gs th
at g
ive
off l
ight
oft
en a
lso
give
off
heat
. Hea
t is
prod
uced
by
mec
hani
cal a
nd
elec
tric
al m
achi
nes,
and
any
time
one
thin
g ru
bs a
gain
st s
omet
hing
els
e.
FO
Whe
n w
arm
er th
ings
are
put
with
coo
ler
ones
, the
war
m o
nes
lose
hea
t and
the
cool
on
es g
ain
it un
til th
ey a
re a
ll at
the
sam
e te
mpe
ratu
re. A
war
mer
obj
ect c
an w
arm
a
cool
er o
ne b
y co
ntac
t or a
t a d
ista
nce.
FF
FF
Som
e m
ater
ials
con
duct
hea
t muc
h be
tter
th
an o
ther
s. Po
or c
ondu
ctor
s ca
n re
duce
he
at lo
ss.
FF
F
Man
y ev
ents
invo
lve
tran
sfer
of e
nerg
y fr
om
one
obje
ct to
ano
ther
.F
FO
OO
OF
F
Mos
t pro
cess
es in
volv
e th
e tr
ansf
er o
f en
ergy
from
one
sys
tem
to a
noth
er.
Ener
gy c
an b
e tr
ansf
erre
d in
diff
eren
t way
s. (G
rade
s 6-
8)
FF
OO
OO
FF
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
5 o
f 10)
2�1ENERGY | bENChmaRks |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BEn
ergy
app
ears
in d
iffer
ent f
orm
s. M
otio
n en
ergy
is a
ssoc
iate
d w
ith th
e sp
eed
of a
n ob
ject
. Hea
t ene
rgy
is a
ssoc
iate
d w
ith th
e te
mpe
ratu
re o
f an
obje
ct. G
ravi
tatio
nal
ener
gy is
ass
ocia
ted
with
the
heig
ht o
f an
obj
ect a
bove
a re
fere
nce
poin
t. El
astic
en
ergy
is a
ssoc
iate
d w
ith th
e st
retc
hing
of
an
elas
tic o
bjec
t. Ch
emic
al e
nerg
y is
as
soci
ated
with
the
chem
ical
com
posi
tion
of a
sub
stan
ce. W
ithin
a s
yste
m, e
nerg
y ca
n be
tran
sfor
med
from
one
form
to a
noth
er.
(Gra
des
6-8)
EF
FF
OO
OO
FF
G. T
he F
orce
s of
Nat
ure
The
eart
h’s
grav
ity p
ulls
any
obj
ect t
owar
d it
with
out t
ouch
ing
it.O
O
5. T
he L
ivin
g En
viro
nmen
t
E. F
low
of M
atte
r and
Ene
rgy
Alm
ost a
ll ki
nds
of a
nim
als’
food
can
be
trac
ed b
ack
to p
lant
s.O
Som
e so
urce
of “
ener
gy” i
s ne
eded
for a
ll or
gani
sms
to s
tay
aliv
e an
d gr
ow.
OO
6. T
he H
uman
Org
anis
m
C. B
asic
Fun
ctio
n
From
food
, peo
ple
obta
in e
nerg
y an
d m
ater
ials
for b
ody
repa
ir an
d gr
owth
. The
in
dige
stib
le p
arts
of f
ood
are
elim
inat
ed.
OO
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
6 o
f 10)
| ENERGY | bENChmaRks 2�2
Ben
chm
arks
(Page
7 o
f 10)
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BE.
Phy
sica
l Hea
lth
Food
pro
vide
s en
ergy
and
mat
eria
ls fo
r gr
owth
and
repa
ir of
bod
y pa
rts.
Vita
min
s an
d m
iner
als,
pres
ent i
n sm
all a
mou
nts
in fo
od, a
re e
ssen
tial t
o ke
ep e
very
thin
g w
orki
ng w
ell.
As
peop
le g
row
up,
the
amou
nts
and
kind
s of
food
and
exe
rcis
e ne
eded
by
the
body
may
cha
nge.
OO
8. T
he D
esig
ned
Wor
ld
B. M
ater
ials
and
Man
ufac
turin
g
The
choi
ce o
f mat
eria
ls fo
r a jo
b de
pend
s on
th
eir p
rope
rtie
s an
d ho
w th
ey in
tera
ct w
ith
othe
r mat
eria
ls. (
Gra
des
6-8)
FO
C. E
nerg
y So
urce
s an
d U
ses
Mov
ing
air a
nd w
ater
can
be
used
to ru
n m
achi
nes.
FF
O
The
sun
is th
e m
ain
sour
ce o
f ene
rgy
for
peop
le a
nd th
ey u
se it
in v
ario
us w
ays.
The
ener
gy in
foss
il fu
els
such
as
oil a
nd c
oal
com
es fr
om th
e su
n in
dire
ctly
, bec
ause
the
fuel
s co
me
from
pla
nts
that
gre
w lo
ng a
go.
OO
Som
e en
ergy
sou
rces
cos
t les
s th
an o
ther
s an
d so
me
caus
e le
ss p
ollu
tion
than
oth
ers.
FO
Peop
le tr
y to
con
serv
e en
ergy
in o
rder
to
slo
w d
own
the
depl
etio
n of
ene
rgy
reso
urce
s an
d/or
to s
ave
mon
ey.
OF
Ener
gy c
an c
hang
e fr
om o
ne fo
rm to
an
othe
r, al
thou
gh in
the
proc
ess
som
e en
ergy
is a
lway
s co
nver
ted
to h
eat.
Som
e sy
stem
s tr
ansf
orm
ene
rgy
with
less
loss
of
heat
than
oth
ers.
(Gra
des
6-8)
FO
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
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vers
ity P
ress
, 199
3.
2�3ENERGY | bENChmaRks |
Ben
chm
arks
(Page
8 o
f 10)
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
B9.
The
Mat
hem
atic
al W
orld
A. N
umbe
rs
Whe
n pe
ople
car
e ab
out w
hat i
s be
ing
coun
ted
or m
easu
red,
it is
impo
rtan
t for
th
em to
say
wha
t the
uni
ts a
re (t
hree
de
gree
s Fa
hren
heit
is d
iffer
ent f
rom
thre
e ce
ntim
eter
s, th
ree
mile
s fr
om th
ree
mile
s pe
r hou
r).
OO
OO
Mea
sure
men
ts a
re a
lway
s lik
ely
to g
ive
slig
htly
diff
eren
t num
bers
, eve
n if
wha
t is
bein
g m
easu
red
stay
s th
e sa
me.
O
OF
B. S
ymbo
lic R
elat
ions
hips
Tabl
es a
nd g
raph
s ca
n sh
ow h
ow v
alue
s of
one
qua
ntity
are
rela
ted
to v
alue
s of
an
othe
r.F
OF
O
C. S
hape
s
Gra
phic
al d
ispl
ay o
f num
bers
may
mak
e it
poss
ible
to s
pot p
atte
rns
that
are
not
ot
herw
ise
obvi
ous,
such
as
com
para
tive
size
an
d tr
ends
.
FO
FF
D. U
ncer
tain
ty
Som
e pr
edic
tions
can
be
base
d on
wha
t is
kno
wn
abou
t the
pas
t, as
sum
ing
that
co
nditi
ons
are
pret
ty m
uch
the
sam
e no
w.
OO
O
E. R
easo
ning
One
way
to m
ake
sens
e of
som
ethi
ng is
to
thin
k ho
w it
is li
ke s
omet
hing
mor
e fa
mili
ar.
O
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
| ENERGY | bENChmaRks 2�4
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
B11
. Com
mon
The
mes
A. S
yste
ms
In s
omet
hing
that
con
sist
s of
man
y pa
rts,
the
part
s us
ually
influ
ence
one
ano
ther
.O
B. M
odel
s
Geo
met
ric fi
gure
s, nu
mbe
r seq
uenc
es,
grap
hs, d
iagr
ams,
sket
ches
, num
ber l
ines
, m
aps,
and
stor
ies
can
be u
sed
to re
pres
ent
obje
cts,
even
ts, a
nd p
roce
sses
in th
e re
al
wor
ld, a
lthou
gh s
uch
repr
esen
tatio
ns c
an
neve
r be
exac
t in
ever
y de
tail.
OO
OO
OO
OO
C. C
onst
ancy
and
Cha
nge
Thin
gs c
hang
e in
ste
ady,
repe
titiv
e, o
r irr
egul
ar w
ays-
or s
omet
imes
in m
ore
than
on
e w
ay a
t the
sam
e tim
e. O
ften
the
best
w
ay to
tell
whi
ch k
inds
of c
hang
e ar
e ha
ppen
ing
is to
mak
e a
tabl
e or
gra
ph o
f m
easu
rem
ents
.
OO
O
12. H
abit
s of
Min
d
A. V
alue
s an
d A
ttitu
des
Keep
reco
rds
of th
eir i
nves
tigat
ions
and
ob
serv
atio
ns a
nd n
ot c
hang
e th
e re
cord
s la
ter.
OO
OO
OO
OO
OO
OO
Offe
r rea
sons
for t
heir
findi
ngs
and
cons
ider
re
ason
s su
gges
ted
by o
ther
s.O
OO
OO
C. M
anip
ulat
ion
and
Obs
erva
tion
Keep
a n
oteb
ook
that
des
crib
es
obse
rvat
ions
mad
e, c
aref
ully
dis
tingu
ishe
s ac
tual
obs
erva
tions
from
idea
s an
d sp
ecul
atio
ns a
bout
wha
t was
obs
erve
d, a
nd
is u
nder
stan
dabl
e w
eeks
or m
onth
s la
ter.
OO
OO
OO
OO
OO
O
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
9 o
f 10)
2��ENERGY | bENChmaRks |
LEG
END
: F=
Focu
s in
Les
son
O
=Ong
oing
Dev
elop
men
t
E=Ea
rly In
trod
uctio
nLE
SSO
N
BEN
CHM
ARK
12
34
56
78
9SB
A1
SBA
2SB
A3
SBA
4SR
BD
. Com
mun
icat
ion
Skill
s
Writ
e in
stru
ctio
ns th
at o
ther
s ca
n fo
llow
in
carr
ying
out
a p
roce
dure
.O
Mak
e sk
etch
es to
aid
in e
xpla
inin
g pr
oced
ures
or i
deas
.O
F
Use
num
eric
al d
ata
in d
escr
ibin
g an
d co
mpa
ring
obje
cts
and
even
ts.
OO
OO
O
Org
aniz
e in
form
atio
n in
sim
ple
tabl
es a
nd
grap
hs a
nd id
entif
y re
latio
nshi
ps th
ey
reve
al. (
Gra
des
6-8)
FF
O
Loca
te in
form
atio
n in
refe
renc
e bo
oks,
back
issu
es o
f new
spap
ers
and
mag
azin
es,
com
pact
dis
ks, a
nd c
ompu
ter d
atab
ases
. (G
rade
s 6-
8)
FO
E. C
ritic
al-R
espo
nse
Skill
s
Reco
gniz
e w
hen
com
paris
ons
mig
ht n
ot b
e fa
ir be
caus
e so
me
cond
ition
s ar
e no
t kep
t th
e sa
me.
OO
OF
Am
eric
an A
ssoc
iatio
n fo
r the
Adv
ance
men
t of S
cien
ce (P
roje
ct 2
061)
. Ben
chm
arks
for S
cien
ce L
itera
cy. N
ew Y
ork:
Oxf
ord
Uni
vers
ity P
ress
, 199
3.
Ben
chm
arks
(Page
10
of 1
0)
Energy Unit Teacher Masters: Table of Contents
Introductory Letter to Families
Welcome to the Energy Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2
Assessments
Energy Assessment 1: Energy Forms and Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Energy Assessment 2: Heat Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Energy Assessment 3: Energy Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Energy Assessment 4: Cooperative Group Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Energy Assessment 5: Planning and Designing an Invention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Energy Assessment 6: Recording and Analyzing Data and Making Conclusions . . . . . . . . . . . . . .8
Note Recording Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–10
Teacher Masters
Request for Materials (Lessons 1, 4, and 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Energy Walk Reference Sheet (Lesson 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12–13
Identifying Energy Forms (Lesson 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Energy Station Directions (Lesson 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15–18
Identifying Energy Transfers (Lesson 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
How to Build a Balloon Boat (Lesson 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20–21
How to Build a Rubber Band Boat (Lesson 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22–23
How to Build a Secret Potion Boat (Lesson 4). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24–26
Consumer Math (Lesson 8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27–29
Automatic Sunscreen Applicator and Alarm (Lesson 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30–31
Measuring Accurately (SBA 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Calibrating Thermometers (SBA 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33–34
Graphing the Height of a Fern (SBA 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Setting Up a Fair Test (SBA 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36–39
Energy Unit Teacher Masters: Table of Contents, page 1 of 2
ISBN 1-59192-287-92 3 4 5 6 7 8 9 10-P001-17 16 15 14 13 12 11 10 09 082009 Edition. Copyright © 2005 Chicago Science Group. All Rights Reserved.
Energy Teacher Master 2
Family Links
Energy Log (Lesson 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Toy Box Science (Lesson 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Heat Energy Transfers (Lesson 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Kitchen Conductors (Lesson 6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Criteria for Insulators (Lesson 7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Insulator Scavenger Hunt (Lesson 7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Is Your Home Energy-Efficient? (Lesson 8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
My Invention (Lesson 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Energy Unit Teacher Masters: Table of Contents, page 2 of 2
Energy Teacher Master 3Assessment 1: Energy Forms and Transfers
Energy Assessment 1: Energy Forms and TransfersAs you evaluate students’ discussions and work, determine how well they understand the following concepts.
Assessment Criteria:
Students’ Names
A. Energy is observable all around us and can take many forms.
B. Energy moves from place to place and sometimes changes forms to make things happen.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
Energy Teacher Master 15Energy Station Directions (Lesson 3), page 1 of 4
Energy Station Directions
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 1: Pop-up Toy1. Press down gently on the toy’s head until the suction cup sticks to the base.
2. Watch and wait.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 2: Dominoes1. Line up the dominoes—with dominoes placed upright on their shortest end—
so that the space between every two dominoes is slightly less than the length of one domino.
2. Gently tap the first domino in the line so it falls in the direction of the second domino.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 3: Sparking Wheel1. Hold the stem of the toy between your index and middle fingers.
2. Pump the base several times with your thumb.
3. Observe what happens.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 4: Energy Ball1. Touch both metal strips on the ball at the same time.
2. Look and listen.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Energy Teacher Master 16
Energy Station Directions
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 5: Hand-held Electrical Generator1. Hold the generator firmly in one hand.
2. Use your other hand to turn the crank handle.
3. Observe.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 6: Spinning Top1. Begin by looking at the top that has been taken apart. Can you make its light
turn on?
2. Now look at the top that has not been taken apart. Fit the top into its base so there is no gap between the two pieces.
3. Twist the base clockwise four times.
4. Hold the top upright (with the button on top) slightly above the center of the box lid and push the button to release the top.
5. Watch what happens. How do you explain what you see?
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 7: Radiometer1. Place the radiometer on a flat surface under a light source.
2. What happens?
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Energy Station Directions (Lesson 3), page 2 of 4
Energy Teacher Master 17Energy Station Directions (Lesson 3), page 3 of 4
Energy Station Directions
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 8: Ball1. Hold the ball in your hand at about waist level.
2. Drop the ball.
3. Catch the ball. (This is a very important step!)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 8 (alternative): Pull-back Toy Car1. Hold the car in one hand and place the wheels on a flat, level surface.
2. Pull the car backwards about 1/2 meter, or until you hear a clicking sound. DO NOT OVERWIND.
3. Release and observe.
Energy Teacher Master 18Energy Station Directions (Lesson 3), page 4 of 4
Energy Station Directions
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Station 9: Magic Bracelet1. Place your hands in the paper bag and slip the beaded bracelet onto your wrist.
2. Remove your hand from the bag and notice how the bracelet looks.
3. Position your wrist so that sunlight or the clamp light shines on the bracelet. Keep your hand a safe distance from the clamp light to prevent burns.
4. Look carefully at the beads on the bracelet. What is happening?
5. Place the bracelet back in the paper bag for the next group.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Name: Date:
Energy Teacher Master 41Family Link: Toy Box Science (Lesson 3)
Family Link with Science—Homework
Toy Box ScienceToday in class you mapped the energy transfers that occurred when you operated several different toys. Now think about your own toys. Do any of them require an energy transfer in order to work?
Select a toy that runs as a result of energy transfers and answer the following questions.
1. What is your toy called? _________________________________________
2. What does your toy do? _________________________________________
_____________________________________________________________
3. Describe, or use arrows to map, how energy is transferred to operate your toy.
Bonus Activity “Wintergreens in the Dark”1. Bring wintergreen-flavored Lifesavers® for you and a friend or family member
into a dark room such a closet. Allow your eyes to adjust to the dark. Look carefully at each other’s mouths as you both chew your Lifesaver. Use the space below to describe what happened.
2. Describe the energy transfer(s) that took place as you chewed the Lifesaver.
Please return to class by ____________________________.
Energy Unit Visuals: Table of Contents
Overhead Transparencies
Energy Talk (Lesson 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Energy Cards (Lesson 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–3
Mapping Energy Transfers (Lessons 3 and 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Exploring How Well Different Materials Slow Heat Energy Transfer (Lesson 7) . . . . . . . . . . . . . . . .5
100W and 25W Light Bulbs (Lesson 8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
25W and 26W Light Bulbs (Lesson 8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
100W and 26W Light Bulbs (Lesson 8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Automatic Sunscreen Applicator and Alarm (Lesson 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–10
Comparing Graphs (SBA 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Graphing the Height of a Fern (SBA 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Photo Cards
Photo “Energy” Cards (Lesson 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–28
ISBN 1-59192-288-7 2 3 4 5 6 7 8 9 10-P001-17 16 15 14 13 12 11 10 09 08 2009 Edition. Copyright © 2005 Chicago Science Group. All Rights Reserved.
2009 Edition. Copyright © 2005 Chicago Science Group. All Rights Reserved.www.sciencecompanion.com
Mapping Energy TransfersDemonstration:
Use arrows and words to show what types of energy transfers occurred as your teacher
operated the item listed above.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Overhead Transparency: Mapping Energy Transfers (Lessons 3 and 4)
Energy Visual 4
ENERGY | TABLE OF CONTENTS| 3
Table of ContentsIntroduction
Assessment Philosophy........................................................................ 5 Assessment Materials........................................................................... 8
Content Rubrics and Opportunity OverviewsEnergy Forms and Transfers Rubric 1................................................16 Energy Forms and Transfers Opportunities Overview........................17 Heat Energy Rubric 2..........................................................................18 Heat Energy Opportunities Overview..................................................19 Energy Efficiency Rubric 3..................................................................20 Energy Efficiency Opportunities Overview..........................................21
Skills and Attitudes Checklists and Self-AssessmentsCooperative Group Work: Checklist....................................................24 Working in a Group: Self-Assessment ................................................25 Recording and Analyzing Data and Making Conclusions: Checklist ..26 Collecting Data and Making Conclusions: Self-Assessment ..............27 Planning and Designing an Invention: Checklist.................................28
Performance Tasks and Evaluation Guidelines What is Energy? Cluster (Lessons 1-2): Lighting Up the Sky ....................................................................30 Energy Transfers Cluster (Lessons 3-4): Johnnie’s Bat ..............................................................................31 Riding Bikes................................................................................32 Heat Energy Transfers Cluster (Lessons 5-7): Hot Chocolate.............................................................................33 Baking Cookies...........................................................................34 What to Wear?............................................................................35 Applying Energy Smarts Transfers Cluster (Lessons 8-9): Household Lighting.....................................................................36 Unit Assessment: Chain Reaction Invention ...........................................................37
Quick Check Items and Answer KeysWhat is Energy? Cluster (Lessons 1-2) ..............................................40 Energy Transfers Cluster (Lessons 3-4) .............................................41 Heat Energy Transfers Cluster (Lessons 5-7) ....................................43 Applying Energy Smarts (Lessons 8-9) ..............................................46
Assessment Masters What is Energy? Cluster: Lighting Up the Sky ....................................................................50 Quick Check Items .....................................................................51
4 | ENERGY | TABLE OF CONTENTS
Energy Transfers Cluster: Johnnie’s Bat ..............................................................................52 Riding Bikes................................................................................53 Quick Check Items .....................................................................54 Heat Energy Transfers Cluster: Hot Chocolate.............................................................................56 Baking Cookies...........................................................................57 What to Wear?............................................................................58 Quick Check Items .....................................................................59 Applying Energy Smarts Cluster: Household Lighting.....................................................................62 Quick Check Items .....................................................................63
16 | ENERGY | CONTENT RUBRICS AND OPPORTUNITIES OVERVIEWS
Rubric 1: Energy Forms and Transfers Criterion A(Lessons 1—2, 9)
Criterion B(Lessons 3 4, 9)
Energy is observable all around us and can take many forms.
Energy moves from place to place and sometimes changes forms to make things happen.
4 - Exceeds Expectations
Explores content beyond the level presented in the lessons.
Understands at a secure level (see box below) and can give examples of objects that possess more than one form of energy.
Understands at a secure level (see box below) and can apply their understanding to new situations (e.g., toys brought from home, improvements on boats).
3 - Secure(MeetsExpectations)
Understands content at the level presented in the lessons and does not exhibit misconceptions.
Can identify many specific forms of energy in their environment.
Recognizes that energy moves from place to place and sometimes changes form to make things happen.
2 - Developing(Approaches Expectations)
Shows an increasing competency with lesson content.
Intuitively knows that certain objects have energy but doesn’t identify the energy as any specific form.
Has an incomplete understanding of how energy transfers make something happen(e.g., knows that energy transfers but not that sometimes energy changes form)
1 - Beginning
Has no previous knowledge of lesson content.
Cannot observe or identify energy in one’s surroundings.
Does not know that energy is required to make things happen.
ENERGY | CONTENT RUBRICS AND OPPORTUNITIES OVERVIEWS | 17
Opportunities Overview: Energy Forms and Transfers
This table highlights opportunities to assess the criteria on Rubric 1: Energy Forms and Transfers. It does not include every assessment opportunity; feel free to select or devise other ways to assess various criteria.
Criterion A(Lessons 1—2, 9)
Criterion B(Lessons 3—4, 9)
Pre
and
Form
ativ
e O
ppor
tuni
ties
Lesson 1:- Journal writing - Reflective discussion
Lesson 2: - Teacher Master “Identifying Energy Forms”
- Synthesizing discussion Lesson 9:
- Exploration, Session 2 - Journal writing
Lesson 3:- Introductory discussion - Exploration - Science notebook pages 4–13 - Family Link “Toy Box Science” - Journal writing
Lesson 4: - Science notebook page 15
Lesson 9:- Exploration, Session 2 - Journal writing
Performance Tasks
What Is Energy? ClusterLighting Up the Sky, page 30
Unit Assessment Chain Reaction Invention, page 37
Energy Transfers Cluster Johnnie’s Bat, page 31 Riding Bikes, page 32
Unit Assessment Chain Reaction Invention, page 37
Quick Check Items
Sum
mat
ive
Opp
ortu
nitie
s
What Is Energy? ClusterPage 40: items 1, 2
Heat Energy Transfers ClusterPage 43: item 1
Energy Transfers ClusterPages 41-42: items 1-5
ENERGY | PERFORMANCE TASK EVALUATION GUIDELINES | 31
Johnnie’s Bat Energy Transfers Cluster (Lesson 3-4)
Each year, Mr. Dracula throws a Halloween party. He asks every student to bring a toy to share. This year, Johnnie’s flying bat was the hit of the party. When he arrived at Mr. Dracula’s classroom, he hung the bat from the center of the ceiling with a piece of string. Once turned on (it ran on batteries), the bat flew around in circles, flashed its lit up red eyes, and screeched loudly.
After several flashing and screeching events, the string broke and the bat crashed to the floor.
Use words from the word bank and arrows to map what types of energy transfers occurred with Johnnie’s bat.
TEACHER NOTES:Use this assessment after teaching Lesson 3.
You might encourage your students to use different kinds of lines to represent two different maps. For example, they could use a solid line for the flying bat and a dotted line for the falling bat. They could also use different colors—one for the flying bat and one for the falling bat.
EVALUATION GUIDELINES:When evaluating student answers, consider whether they include some of the following elements in their written explanations:
There are many different energy transfers taking place at the same time. For example, when the bat is flying, chemical energy (from battery) transfers to motion energy (bat flying), light energy (eye’s flashing), and sound energy (bat screeching). When the bat falls, gravitational energy transfers to motion energy and possibly ends with sound energy (as it hits the floor).
Energy Forms electrical chemical motion elastic gravitational heat light sound
motion
chemical
light sound
gravitational
32 | ENERGY | PERFORMANCE TASK EVALUATION GUIDELINES
Riding Bikes Energy Transfers Cluster (Lessons 3-4)
Hallie loves riding bikes. She loves how she can pedal really hard to go fast, or not pedal at all, and just gently coast along. She loves being in control of how long it takes her to get somewhere. Hallie thinks of her bike as one of the most amazing machines because it uses no energy to get her from place to place.
Do you agree with Hallie that a bike is a machine? Explain your answer.
Do you agree that it uses no energy? Explain your reasoning.
TEACHER NOTE:Use this assessment after teaching Lesson 4.
EVALUATION GUIDELINES:When evaluating student answers, consider whether they include the following elements in their written explanations:
Yes, the bike is a machine.
The bike does use energy because a bike could not move without energy transfers. All change requires energy.
Muscles or bodies use chemical energy (from the food we eat) and transfers it to the motion energy of our legs to make the bike move. Bikes on a hill or slope have gravitational energy that transfers to motion energy when a bike coasts downhill. All of these transfers help Hallie get from one place to another.
ENERGY | QUICK CHECK ANSWER KEYS | 41
Energy Transfers Cluster Quick Check Items
TEACHER NOTE: The following questions relate to the Energy Transfers cluster. Use them after teaching the entire cluster, or select the applicable questions immediately following each lesson. You can also compile Quick Check items into an end-of-unit assessment.
1. (Lesson 3) True or False? If false, rewrite the statements to make them true.
a. Energy is required for change to happen. ___________ true
b. Energy cannot move from place to place. ___________ false
Energy moves from place to place, or object to object, all of the time.
2. (Lesson 3) Which sequence best describes the energy transfers in a solar propeller?
a. light chemical sound
b. light chemical motion
c. light electrical motion
d. no transfers take place
3. (Lesson 3) In question 2, what happened to the energy during each transfer?
a. The energy changed form as it transferred.
b. Nothing happened. The energy form stayed the same.
c. The energy moved but did not change forms.
4. (Lesson 4) Put an “X” next to any item that is a machine.
X_______ car
X_______ rowboat
X_______ scissors
X_______ lamp
Date:
�
Hello Scientist,
Welcome to the Energy unit. This notebook is your place to
record discoveries about energy. Like all scientists, you will
wonder, think, try, observe, record, and discover. As you do
so, it is important to keep a record of your work. Your ques-
tions, investigations, answers, and reflections can then be
shared and returned to at any time.
We know much about science, but there is much more to be
learned. Your contributions start here.
Enjoy, take pride in, and share your discoveries—science
depends on scientists like you!
ISBN 1-59192-285-2
2 3 4 5 6 7 8 9 10-P001-17 16 15 14 13 12 11 10 09 08
2009 Edition. Copyright © 2005 Chicago Science Group. All Rights Reserved.
Hello Scientist
ANNOTATED TEACHER GUIDE
Teacher Guide Annotations supplied in RED for ease of use.
ISBN 1-59192-286-0
2 3 4 5 6 7 8 9 10-P001-17 16 15 14 13 12 11 10 09 08
2009 Edition. Copyright © 2005 Chicago Science Group. All Rights Reserved.
Date:
�
Mapping Energy Transfers
Demonstration: Solar Propeller
Use arrows and words to show what types of energy transfers occurred as your teacher oper-ated the item listed above.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
Students can start their map from any star on the page.
light
electrical
motion
light energy from the sun hits the solar panel
electrical energy powers the motor, making the propeller spin
Date:
�
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
Pop-up toy
Example responses for each toy station are included on the following pages, although the students will not necessarily complete the stations in the order presented in this guide.
motion
elastic
motion
hand moves and pushes down on pop-up toy to store elastic energy
the spring in the pop-up toy extends, making the toy move and pop into the air
Date:
�
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
motion
motion
gravitational
hand knocks down domino
domino falls
Dominoes
motion
falling domino hits next domino
Date:
�
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
Sparking-wheel
motion
motion
heat
hand pumps wheel
surfaces in toy rub against each other
light
tiny glowing pieces of the surfaces fly off as “sparks”
Date:
�
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
chemical
electrical
light
connection of electrical circuit allows chemical energy from the battery to transfer to electrical energy
electricity makes ball light up
Energy ball
sound
electricity creates sound
Date:
�
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
Hand-held electrical generator
motion
electrical
light
hand turns crank, generating an electrical current
electricity makes the bulb light up
gears rub together as crank handle is turned
sound
Date:
�0
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
motion
elastic
motion
top is twisted
top is released and spins
Spinning top
light
spinning causes top to light up
There is a chemical energy to electrical energy component in the spinning top. The spinning causes the battery’s electrodes to connect, which transfers the battery’s chemical energy to electrical energy and then to light energy. However, students may not identify all of these energy transfers.
Date:
��
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
Radiometer
light
heat
motion
black surfaces absorb heat
top spins
Date:
��
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
gravitational
motion
elastic
ball is dropped
ball hits floor
Ball
motion
ball bounces up
Date:
��
Mapping Energy Transfers
Type of Toy:
Use arrows and words to show how energy was transferred in this toy. You can use as many of the shapes as you need for your map. You can also draw more shapes if you need them.
Energy Forms
Electrical Chemical Motion Elastic Gravitational Heat Light Sound
Mapping Energy Transfers (Lesson 3)
Magic bracelet
light
chemical
light energy from the sun hits the beads, making them change color
EnergyStudent Reference Book
Writers
Belinda Basca and Martha Sullivan
Developers
Colleen Bell, Diane Bell, Cindy Buchenroth-Martin, and Catherine Grubin
Editors
Rachel Burke and Wanda Gayle
Pedagogy and Content Advisors
Jean Bell, Max Bell, Nick Cabot*, Debbie Clement*, Josie Grotenhuis*, Tim Strains*, and Robert Ward
*Scientists or teachers who gave advice but are not part of the Chicago Science Group.
Field Test Teachers
Joyce Berry, Suze Bodwell, Jim Elwell, Nancy Florig, David Grelecki, Matt Laughlin, Lisette Mirabile,
Valerie Powell, Jen Ryan, Chris Sanborn, Kitty Skow, Jane Stephenson, Will Whitlock, and Nancy Zordan
Book Design and Production
Happenstance Type-O-Rama; Picas & Points, Plus (Carolyn Loxton)
www.sciencecompanion.com
2009 Edition
Copyright © 2005 Chicago Science Group.
All Rights Reserved
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part of this publication may be reproduced or distributed in any form or by any means or stored in a
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SCIENCE COMPANION®, EXPLORAGEAR®, the CROSSHATCH Design™ and the WHEEL
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ISBN 1-59192-397-2
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Table of Contents
Chapter 1: Recognizing Forms of Energy . . . . . . . . . . . . . . . . . . . . . . . . . 1
Where Can You Find Energy? . . . . . . . . . . . . . . . . . . . . 1
Forms of Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Motion Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Chemical Energy . . . . . . . . . . . . . . . . . . . . . . . . . 3
Gravitational Energy. . . . . . . . . . . . . . . . . . . . . . . 4
Elastic Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Heat Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Light Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical Energy . . . . . . . . . . . . . . . . . . . . . . . . . 8
Sound Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Energy Makes Things Happen . . . . . . . . . . . . . . . . . . 10
Chapter 2: Recognizing Energy Transfers . . . . . . . . . . . . . . . . . . . . . . . .13
Energy Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Energy Transfers and the Natural World . . . . . . . . . . . . . 14
Energy Transfers from the Sun. . . . . . . . . . . . . . . . . 14
Energy Transfers from Inside the Earth . . . . . . . . . . . . 17
Energy Transfers Between Living Things . . . . . . . . . . . 19
Frequently Asked Questions. . . . . . . . . . . . . . . . . . . . 21
Does Energy Change When It Is Transferred? . . . . . . . . . 21
How Can I Tell That Energy Is Being Transferred in the Natural World? . . . . . . . . . . . . . . . . . . . . 22
Table of Contents
Chapter 1: Recognizing Forms of Energy . . . . . . . . . . . . . . . . . . . . . . . . . 1
Where Can You Find Energy? . . . . . . . . . . . . . . . . . . . . 1
Forms of Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Motion Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Chemical Energy . . . . . . . . . . . . . . . . . . . . . . . . . 3
Gravitational Energy. . . . . . . . . . . . . . . . . . . . . . . 4
Elastic Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Heat Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Light Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical Energy . . . . . . . . . . . . . . . . . . . . . . . . . 8
Sound Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Energy Makes Things Happen . . . . . . . . . . . . . . . . . . 10
Chapter 2: Recognizing Energy Transfers . . . . . . . . . . . . . . . . . . . . . . . .13
Energy Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Energy Transfers and the Natural World . . . . . . . . . . . . . 14
Energy Transfers from the Sun. . . . . . . . . . . . . . . . . 14
Energy Transfers from Inside the Earth . . . . . . . . . . . . 17
Energy Transfers Between Living Things . . . . . . . . . . . 19
Frequently Asked Questions. . . . . . . . . . . . . . . . . . . . 21
Does Energy Change When It Is Transferred? . . . . . . . . . 21
How Can I Tell That Energy Is Being Transferred in the Natural World? . . . . . . . . . . . . . . . . . . . . 22
iii
iv
Chapter 3: Putting Energy Transfers to Use . . . . . . . . . . . . . . . . . . . . . . .25
Machines and Energy Transfers . . . . . . . . . . . . . . . . . . 26
Floating Machines—Boats and Energy Transfers . . . . . . . . . 28
How Do Boats Transfer Energy to Carry People and Things Across Water? . . . . . . . . . . . . . . . . . . . . 28
Machines of Today and Yesterday. . . . . . . . . . . . . . . . . 30
Household Chores in the 18th Century . . . . . . . . . . . . . . 31
Testing Your Energy IQ . . . . . . . . . . . . . . . . . . . . . . 36
Chapter 4: Heat Energy and Temperature—What’s the Difference? . . . . . . .39
Temperature and Heat Energy . . . . . . . . . . . . . . . . . . 39
How a Thermometer Works . . . . . . . . . . . . . . . . . . . . 41
Thermometers Are All Around You . . . . . . . . . . . . . . 41
How a Bulb Thermometer Works . . . . . . . . . . . . . . . 42
Temperature Scales . . . . . . . . . . . . . . . . . . . . . . 43
Chapter 5: Heat Energy Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Identifying Heat Energy Transfers. . . . . . . . . . . . . . . . . 45
Heat Energy Transfers from Warmer to Cooler Objects. . . . . . 50
Chapter 6: Conductors of Heat Energy . . . . . . . . . . . . . . . . . . . . . . . . . .57
Kitchen Conductors . . . . . . . . . . . . . . . . . . . . . . . . 57
Scientific Inventions in Your Kitchen! . . . . . . . . . . . . . 57
Cooking—Harnessing Heat Energy Transfers to Meet Our Needs . . . . . . . . . . . . . . . . . . . . . . . 62
How Well Do Materials Conduct Heat Energy? . . . . . . . . 63
Chapter 7: Insulation to Keep Us Warm . . . . . . . . . . . . . . . . . . . . . . . . .69
Insulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
The Many Types of Insulators . . . . . . . . . . . . . . . . . 69
How Homes Stay Warm . . . . . . . . . . . . . . . . . . . . . . 70
Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
The Dangers of Fiberglass . . . . . . . . . . . . . . . . . . . 73
Alternatives to Fiberglass . . . . . . . . . . . . . . . . . . . 74
How Humans Stay Warm . . . . . . . . . . . . . . . . . . . . . 75
Clothing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Layer Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
How Animals Stay Warm . . . . . . . . . . . . . . . . . . . . . 76
Hair Traps Air . . . . . . . . . . . . . . . . . . . . . . . . . 76
Blubber or Fat . . . . . . . . . . . . . . . . . . . . . . . . . 78
Down Feathers . . . . . . . . . . . . . . . . . . . . . . . . . 80
Chapter 8: Using Energy Efficiently . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
What Makes Something Energy-Efficient? . . . . . . . . . . . . 83
Automobiles and Energy Efficiency . . . . . . . . . . . . . . 83
Household Appliances and Energy Efficiency . . . . . . . . . 84
Light Bulbs and Energy Efficiency . . . . . . . . . . . . . . . 86
Chapter 9: Why Energy Efficiency Matters . . . . . . . . . . . . . . . . . . . . . . . .95
Why Is It Important to Use Things that Are Energy-Efficient? . . 95
Using Energy-Efficient Machines Saves You Money! . . . . . 95
Using Energy-Efficient Things Means Our Energy Resources Will Last Longer! . . . . . . . . . . . . . . . . . 97
Using Energy-Efficient Machines Means a Healthier Planet!. . . . . . . . . . . . . . . . . . . . . . . 98
How Else Can We Use Energy Wisely?. . . . . . . . . . . . . . .102
Using Renewable Energy Sources . . . . . . . . . . . . . . .102
Energy Sources—Pros and Cons . . . . . . . . . . . . . . . .107
Thinking “Green” When Building. . . . . . . . . . . . . . .109
How Can I Be Energy-Efficient? . . . . . . . . . . . . . . . . . .110
Some Easy Things You Can Do . . . . . . . . . . . . . . . .110
Table of Contents
v
Chapter 3: Putting Energy Transfers to Use . . . . . . . . . . . . . . . . . . . . . . .25
Machines and Energy Transfers . . . . . . . . . . . . . . . . . . 26
Floating Machines—Boats and Energy Transfers . . . . . . . . . 28
How Do Boats Transfer Energy to Carry People and Things Across Water? . . . . . . . . . . . . . . . . . . . . 28
Machines of Today and Yesterday. . . . . . . . . . . . . . . . . 30
Household Chores in the 18th Century . . . . . . . . . . . . . . 31
Testing Your Energy IQ . . . . . . . . . . . . . . . . . . . . . . 36
Chapter 4: Heat Energy and Temperature—What’s the Difference? . . . . . . .39
Temperature and Heat Energy . . . . . . . . . . . . . . . . . . 39
How a Thermometer Works . . . . . . . . . . . . . . . . . . . . 41
Thermometers Are All Around You . . . . . . . . . . . . . . 41
How a Bulb Thermometer Works . . . . . . . . . . . . . . . 42
Temperature Scales . . . . . . . . . . . . . . . . . . . . . . 43
Chapter 5: Heat Energy Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Identifying Heat Energy Transfers. . . . . . . . . . . . . . . . . 45
Heat Energy Transfers from Warmer to Cooler Objects. . . . . . 50
Chapter 6: Conductors of Heat Energy . . . . . . . . . . . . . . . . . . . . . . . . . .57
Kitchen Conductors . . . . . . . . . . . . . . . . . . . . . . . . 57
Scientific Inventions in Your Kitchen! . . . . . . . . . . . . . 57
Cooking—Harnessing Heat Energy Transfers to Meet Our Needs . . . . . . . . . . . . . . . . . . . . . . . 62
How Well Do Materials Conduct Heat Energy? . . . . . . . . 63
Chapter 7: Insulation to Keep Us Warm . . . . . . . . . . . . . . . . . . . . . . . . .69
Insulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
The Many Types of Insulators . . . . . . . . . . . . . . . . . 69
How Homes Stay Warm . . . . . . . . . . . . . . . . . . . . . . 70
Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
The Dangers of Fiberglass . . . . . . . . . . . . . . . . . . . 73
Alternatives to Fiberglass . . . . . . . . . . . . . . . . . . . 74
How Humans Stay Warm . . . . . . . . . . . . . . . . . . . . . 75
Clothing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Layer Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
How Animals Stay Warm . . . . . . . . . . . . . . . . . . . . . 76
Hair Traps Air . . . . . . . . . . . . . . . . . . . . . . . . . 76
Blubber or Fat . . . . . . . . . . . . . . . . . . . . . . . . . 78
Down Feathers . . . . . . . . . . . . . . . . . . . . . . . . . 80
Chapter 8: Using Energy Efficiently . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
What Makes Something Energy-Efficient? . . . . . . . . . . . . 83
Automobiles and Energy Efficiency . . . . . . . . . . . . . . 83
Household Appliances and Energy Efficiency . . . . . . . . . 84
Light Bulbs and Energy Efficiency . . . . . . . . . . . . . . . 86
Chapter 9: Why Energy Efficiency Matters . . . . . . . . . . . . . . . . . . . . . . . .95
Why Is It Important to Use Things that Are Energy-Efficient? . . 95
Using Energy-Efficient Machines Saves You Money! . . . . . 95
Using Energy-Efficient Things Means Our Energy Resources Will Last Longer! . . . . . . . . . . . . . . . . . 97
Using Energy-Efficient Machines Means a Healthier Planet!. . . . . . . . . . . . . . . . . . . . . . . 98
How Else Can We Use Energy Wisely?. . . . . . . . . . . . . . .102
Using Renewable Energy Sources . . . . . . . . . . . . . . .102
Energy Sources—Pros and Cons . . . . . . . . . . . . . . . .107
Thinking “Green” When Building. . . . . . . . . . . . . . .109
How Can I Be Energy-Efficient? . . . . . . . . . . . . . . . . . .110
Some Easy Things You Can Do . . . . . . . . . . . . . . . .110
Table of Contents
Table of Contentsvi
Chapter 10: The Spirit of Invention . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Getting Energy to Work for You . . . . . . . . . . . . . . . . . .113
What Does It Take to Be an Inventor? . . . . . . . . . . . . . .114
The Inventive Mind . . . . . . . . . . . . . . . . . . . . . . . .120
Thinking Like an Inventor . . . . . . . . . . . . . . . . . . . .121
Chapter 11: Graphs—Part of a Scientist’s Toolbox . . . . . . . . . . . . . . . . . . 123
Finding the Right Tool for the Job. . . . . . . . . . . . . . . . .123
Bar Graphs . . . . . . . . . . . . . . . . . . . . . . . . . . .123
Line Graphs . . . . . . . . . . . . . . . . . . . . . . . . . .125
Reading Graphs . . . . . . . . . . . . . . . . . . . . . . . . . .128
Appendix A: A Walk Through Energy History . . . . . . . . . . . . . . . . . . . . . . 129
Appendix B: Automatic Sunscreen Applicator and Alarm . . . . . . . . . . . . . . 147
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
��
Recognizing Energy Transfers
Energy Transfers
Every time something happens energy is involved. In fact, it
is the movement of energy from one object to another, one
form to another, or one place to another that brings about all
change. Scientists use the term energy transfer to describe
the movement of energy.
�
Chapter ���
Energy Transfers and the Natural World
Energy transfers are a natural part of our world.
Energy Transfers from the Sun
Energy FactThe Earth receives
only half a billionth
of the energy that
leaves the sun.
As the third planet from the sun, the Earth receives a steady
supply of energy from the sun.
The transfer of energy from the sun to the Earth is responsible
for many of the changes that take place around us.
Weather changes…
The Sun and Its Energy Transfers—The Source of All Weather
Weather Facts• Millions of tons of
water vapor are
evaporated into
the air daily.
• Even the “cleanest”
air found on Earth
contains about
1000 dust particles
per cubic meter
of air.
• About one million
cloud droplets are
contained in one
drop of rain.
• Clouds and precipitation As the sun heats up the
Earth’s waters, some water evaporates and rises into the
atmosphere. Eventually, it cools and condenses on tiny dust
particles to form clouds. The size of the droplets grows until
they are so large that they fall as precipitation.
• Wind The sun does not heat all parts of the Earth equally.
The areas around the equator—the tropics—receive more of
the sun’s energy and are warmer than other parts of the Earth.
Unequal heating leads to the movement of air—wind—from
cooler (higher pressure) regions to warmer (lower pressure)
regions.
• Storms Storms such as hurricanes also result from the
transfer of the sun’s energy to Earth. As large bodies of water
are warmed by the sun, more and more of their water evap-
orates and eventually condenses in the air above. A huge
amount of energy is released into the air as this occurs. The
released energy sets the air in motion, spinning it faster and
wider until a hurricane forms.
��Recognizing Energy Transfers
Energy Transfers and the Natural World
Energy transfers are a natural part of our world.
Energy Transfers from the Sun
Energy FactThe Earth receives
only half a billionth
of the energy that
leaves the sun.
As the third planet from the sun, the Earth receives a steady
supply of energy from the sun.
The transfer of energy from the sun to the Earth is responsible
for many of the changes that take place around us.
Weather changes…
The Sun and Its Energy Transfers—The Source of All Weather
Weather Facts• Millions of tons of
water vapor are
evaporated into
the air daily.
• Even the “cleanest”
air found on Earth
contains about
1000 dust particles
per cubic meter
of air.
• About one million
cloud droplets are
contained in one
drop of rain.
• Clouds and precipitation As the sun heats up the
Earth’s waters, some water evaporates and rises into the
atmosphere. Eventually, it cools and condenses on tiny dust
particles to form clouds. The size of the droplets grows until
they are so large that they fall as precipitation.
• Wind The sun does not heat all parts of the Earth equally.
The areas around the equator—the tropics—receive more of
the sun’s energy and are warmer than other parts of the Earth.
Unequal heating leads to the movement of air—wind—from
cooler (higher pressure) regions to warmer (lower pressure)
regions.
• Storms Storms such as hurricanes also result from the
transfer of the sun’s energy to Earth. As large bodies of water
are warmed by the sun, more and more of their water evap-
orates and eventually condenses in the air above. A huge
amount of energy is released into the air as this occurs. The
released energy sets the air in motion, spinning it faster and
wider until a hurricane forms.
Chapter ���
…and plants grow
Photosynthesis— How the Transfer of Energy from the Sun Feeds the Planet
Almost all living things depend on food created by green plants.
Green plants contain a special pigment (a colored substance) that
captures the sun’s energy. Plants use this energy (light energy) to
create food (chemical energy). The transfer of energy from sun-
light to plant food is called photosynthesis. Plants use the food
they create to grow. When other organisms eat plants, the chemi-
cal energy from the plants is transferred to them.
Energy Transfers from Inside the Earth
Energy is also transferred from deep within the earth’s piping
hot center (4300° C to 7200° C), causing changes that we see
on the surface, such as earthquakes and volcanic eruptions.
These changes are so dramatic that it is very obvious that
energy is being transferred. Heat energy from deep within the
earth is being transferred to the motion energy that literally
“shakes” our world.
0 km(0 mi)
1228 km(763 mi)
3500 km(2174 mi)
6340 km(3939 mi)
6378 km(3963 mi)
Inner Core 4300C to
7200C(7772F to12992F) Mantle
870C to 3700C(1598F to
6692F)
Outer Core3700C to 4300C(6692F to 7772F)
CrustAir Temperature
to 870C(1598F)
��Recognizing Energy Transfers
…and plants grow
Photosynthesis— How the Transfer of Energy from the Sun Feeds the Planet
Almost all living things depend on food created by green plants.
Green plants contain a special pigment (a colored substance) that
captures the sun’s energy. Plants use this energy (light energy) to
create food (chemical energy). The transfer of energy from sun-
light to plant food is called photosynthesis. Plants use the food
they create to grow. When other organisms eat plants, the chemi-
cal energy from the plants is transferred to them.
Energy Transfers from Inside the Earth
Energy is also transferred from deep within the earth’s piping
hot center (4300° C to 7200° C), causing changes that we see
on the surface, such as earthquakes and volcanic eruptions.
These changes are so dramatic that it is very obvious that
energy is being transferred. Heat energy from deep within the
earth is being transferred to the motion energy that literally
“shakes” our world.
0 km(0 mi)
1228 km(763 mi)
3500 km(2174 mi)
6340 km(3939 mi)
6378 km(3963 mi)
Inner Core 4300C to
7200C(7772F to12992F) Mantle
870C to 3700C(1598F to
6692F)
Outer Core3700C to 4300C(6692F to 7772F)
CrustAir Temperature
to 870C(1598F)
Chapter ���
Heat Transfer from Earth’s Core— The Driving Force Behind Earthshaking Events
The center of the earth—its core—is very, very hot! Heat energy
is transferred from the core out towards the earth’s surface. This
heat energy makes a layer of rock beneath the surface—the lower
mantle—so hot that it is semi-molten (able to flow slowly). The
earth’s crust (the thin surface layer of the earth that we walk on)
and solid upper mantle rest on the semi-molten lower mantle. As
the lower mantle slowly flows, shifts occur above it. When there
are big shifts, earthquakes happen.
A fracture (crack) in the ground caused by an earthquake.
Volcanic eruptions are also the result of heat transfers from earth’s
core. When heat from the core is transferred to rock beneath the
earth’s surface, the rock melts. Periodically, this melted (molten)
rock escapes out of cracks in the earth’s surface, sometimes explo-
sively, as when a volcanic eruption occurs.
Lava erupting from a volcano.
Energy Transfers Between Living Things
Some energy transfers happen so slowly, or on such a small
scale, it is hard to see them at all. For example, logs slowly
decompose as their chemical energy transfers to the living
organisms—mushrooms, bacteria, and worms—that feed on it.
For a large log, this can take decades.
A decomposing log.
��Recognizing Energy Transfers
Heat Transfer from Earth’s Core— The Driving Force Behind Earthshaking Events
The center of the earth—its core—is very, very hot! Heat energy
is transferred from the core out towards the earth’s surface. This
heat energy makes a layer of rock beneath the surface—the lower
mantle—so hot that it is semi-molten (able to flow slowly). The
earth’s crust (the thin surface layer of the earth that we walk on)
and solid upper mantle rest on the semi-molten lower mantle. As
the lower mantle slowly flows, shifts occur above it. When there
are big shifts, earthquakes happen.
A fracture (crack) in the ground caused by an earthquake.
Volcanic eruptions are also the result of heat transfers from earth’s
core. When heat from the core is transferred to rock beneath the
earth’s surface, the rock melts. Periodically, this melted (molten)
rock escapes out of cracks in the earth’s surface, sometimes explo-
sively, as when a volcanic eruption occurs.
Lava erupting from a volcano.
Energy Transfers Between Living Things
Some energy transfers happen so slowly, or on such a small
scale, it is hard to see them at all. For example, logs slowly
decompose as their chemical energy transfers to the living
organisms—mushrooms, bacteria, and worms—that feed on it.
For a large log, this can take decades.
A decomposing log.
Chapter ��0
The Food Chain— Energy Transfers Between Living Things
The transfer of energy from one organism to another is called
a food chain. Food chains show how energy is passed from
one organism to another. The arrows between the organisms
show the direction of energy flow. The plant is eaten by the
mouse; the mouse is eaten by the snake; the snake is eaten by
the hawk.
An example of a food chain.
Frequently Asked Questions
Does Energy Change When It Is Transferred?
• Sometimes energy changes form when it is transferred.
For example, when sunlight falls on green plants, energy
is transferred from light to chemical energy.
• Other times energy moves but does not change form.
When a spoon is placed in a bowl of soup, heat energy is
transferred up the spoon handle without changing form.
��Recognizing Energy Transfers
The Food Chain— Energy Transfers Between Living Things
The transfer of energy from one organism to another is called
a food chain. Food chains show how energy is passed from
one organism to another. The arrows between the organisms
show the direction of energy flow. The plant is eaten by the
mouse; the mouse is eaten by the snake; the snake is eaten by
the hawk.
An example of a food chain.
Frequently Asked Questions
Does Energy Change When It Is Transferred?
• Sometimes energy changes form when it is transferred.
For example, when sunlight falls on green plants, energy
is transferred from light to chemical energy.
• Other times energy moves but does not change form.
When a spoon is placed in a bowl of soup, heat energy is
transferred up the spoon handle without changing form.
Chapter ���
How Can I Tell That Energy Is Being Transferred in the Natural World?
Easy, wherever you find change, energy is being transferred!
Seasons Change
The Earth Changes
Living Things Change
��Recognizing Energy Transfers
How Can I Tell That Energy Is Being Transferred in the Natural World?
Easy, wherever you find change, energy is being transferred!
Seasons Change
The Earth Changes
Living Things Change
���
A Walk Through Energy History
Energy has been making things happen since the dawn of
time. Take a walk through time and see how energy has been
used to change our world.
Not all the dates listed in this timeline are exact. Dates that are
approximations will have a “c.” in front of them. The “c.” stands
for “circa” meaning “around” and lets you know that the event
happened around that time.
A
Appendix A��0
4.5 billion years ago Our sun begins shining, warming Earth with solar energy.
3.4 billion years ago Blue-green algae appear on Earth. They are the first plants—
organisms that convert the sun’s energy to food for growth.
1 million years ago Early humans (Homo erectus) use fire for warmth, protection,
and food preparation. Learning how to control fire was one of
the first great energy inventions.
c. 9000 b.c.Humans invent the bow and arrow, harnessing the elastic
energy of a bow to send arrows flying.
c. 3500 b.c.People put animals to use pulling wheeled vehicles in
Mesopotamia (present-day Iraq).
People use solar energy to dry out their crops and collect salt
(which is made by evaporating salt water).
c. 3200 b.c.Early drawings show Egyptian sailboats with a mast and a
single square sail hung from it. Oars are needed when not
traveling in the direction of the wind.
c. 3000 b.c.Humans begin using petroleum (oil from the earth). In
Mesopotamia, rock oil is used in medicines and in the glue
that holds ships and buildings together.
c. 1500 b.c.Polynesian canoes—canoes made of two hulls connected by
crossbeams—carry explorers over the vast waters of the Pacific
Ocean where they establish “new lives” on the Polynesian
Islands.
c. 285 b.c.A lighthouse is built at Alexandria in Egypt. The light from a
fire is reflected off a mirror and can be seen 30 miles away.
c. 200 b.c.Windmills are used to grind grain in Persia (present-day Iran)
and other countries in the Middle East.
���A Walk Through Energy History
4.5 billion years ago Our sun begins shining, warming Earth with solar energy.
3.4 billion years ago Blue-green algae appear on Earth. They are the first plants—
organisms that convert the sun’s energy to food for growth.
1 million years ago Early humans (Homo erectus) use fire for warmth, protection,
and food preparation. Learning how to control fire was one of
the first great energy inventions.
c. 9000 b.c.Humans invent the bow and arrow, harnessing the elastic
energy of a bow to send arrows flying.
c. 3500 b.c.People put animals to use pulling wheeled vehicles in
Mesopotamia (present-day Iraq).
People use solar energy to dry out their crops and collect salt
(which is made by evaporating salt water).
c. 3200 b.c.Early drawings show Egyptian sailboats with a mast and a
single square sail hung from it. Oars are needed when not
traveling in the direction of the wind.
c. 3000 b.c.Humans begin using petroleum (oil from the earth). In
Mesopotamia, rock oil is used in medicines and in the glue
that holds ships and buildings together.
c. 1500 b.c.Polynesian canoes—canoes made of two hulls connected by
crossbeams—carry explorers over the vast waters of the Pacific
Ocean where they establish “new lives” on the Polynesian
Islands.
c. 285 b.c.A lighthouse is built at Alexandria in Egypt. The light from a
fire is reflected off a mirror and can be seen 30 miles away.
c. 200 b.c.Windmills are used to grind grain in Persia (present-day Iran)
and other countries in the Middle East.
Appendix A���
c. 100 b.c. Waterwheels are used in what is now central Turkey.
One-wheeled carts (wheelbarrows) are invented in China.
a.d. 79 Mt. Vesuvius erupts in Italy and buries the towns of
Herculaneum and Pompeii.
c. a.d. 800 Vikings use longboats—boats with long hulls (longer hulls
provide more room for oars and rowers than short hulls)—to
carry warriors and weapons swiftly over the waters of the North
Atlantic and northern Europe. The Vikings invade Northern
Europe for hundreds of years with the help of these ships.
c. a.d. 1000 Natural gas wells are drilled in China. The gas flows through
bamboo tubes (the first known “pipelines”), possibly providing
the heat needed to make porcelain.
a.d. 1044A man named Wu Ching Tsao Yao of China writes the first
known recipe for making saltpeter, the main ingredient in the
gunpowder still used in today’s fireworks.
a.d. 1201The deadliest earthquake in history, which killed 1.1 million
people, strikes Egypt and Syria.
c. 1470–1510Leonardo da Vinci, an Italian artist and inventor, sketches
plans for inventions hundreds of years before they are actually
made. They include a bicycle, a flying machine, a helicopter, a
propeller, and a parachute.
c. 1600–1700Despite its smoke and fumes, coal replaces wood as the most
common way of heating homes in Europe.
1610Galileo Galilei describes the motion of the planets around
the sun.
���A Walk Through Energy History
c. 100 b.c. Waterwheels are used in what is now central Turkey.
One-wheeled carts (wheelbarrows) are invented in China.
a.d. 79 Mt. Vesuvius erupts in Italy and buries the towns of
Herculaneum and Pompeii.
c. a.d. 800 Vikings use longboats—boats with long hulls (longer hulls
provide more room for oars and rowers than short hulls)—to
carry warriors and weapons swiftly over the waters of the North
Atlantic and northern Europe. The Vikings invade Northern
Europe for hundreds of years with the help of these ships.
c. a.d. 1000 Natural gas wells are drilled in China. The gas flows through
bamboo tubes (the first known “pipelines”), possibly providing
the heat needed to make porcelain.
a.d. 1044A man named Wu Ching Tsao Yao of China writes the first
known recipe for making saltpeter, the main ingredient in the
gunpowder still used in today’s fireworks.
a.d. 1201The deadliest earthquake in history, which killed 1.1 million
people, strikes Egypt and Syria.
c. 1470–1510Leonardo da Vinci, an Italian artist and inventor, sketches
plans for inventions hundreds of years before they are actually
made. They include a bicycle, a flying machine, a helicopter, a
propeller, and a parachute.
c. 1600–1700Despite its smoke and fumes, coal replaces wood as the most
common way of heating homes in Europe.
1610Galileo Galilei describes the motion of the planets around
the sun.
Appendix A���
1687 Isaac Newton publishes the Principia—thought to be one of the
greatest scientific books of all time—in which he presents his
theory of gravitation (every particle of matter attracts every other
particle). He also publishes his three Laws of Motion—laws that
describe and predict the motion of all objects on Earth. Newton
also wrote about the behavior of light, including how it can be
divided into colors by a glass prism.
1690 The clarinet, one example of sound energy being used to make
music, was invented in Germany.
1714 The mercury thermometer is introduced by Gabriel Fahrenheit.
Earlier thermometers, which used air instead of mercury, were
not as dependable since they were affected by atmospheric
changes. Atmospheric changes had no effect on the mercury
used to indicate temperature in Fahrenheit’s thermometer.
c. 1750Benjamin Franklin figures out that lightening is actually static
electricity. He also invents a very efficient stove for heating homes.
1769James Watt patents the first efficient steam engine.
1781The stagecoach carries passengers from place to place
throughout the world.
1787On the Delaware River, John Fitch makes the first successful
steamboat voyage.
1800sThe first iceboxes (the earliest “refrigerators”) are used in
homes. They are wooden boxes lined with tin or zinc and
insulated with materials such as cork, sawdust, and seaweed.
These early iceboxes are used to hold blocks of ice and “refrig-
erate” food. A drip pan underneath, which collects melted ice
water, has to be emptied daily.
1801Allesandro Volta creates the first electric battery.
���A Walk Through Energy History
1687 Isaac Newton publishes the Principia—thought to be one of the
greatest scientific books of all time—in which he presents his
theory of gravitation (every particle of matter attracts every other
particle). He also publishes his three Laws of Motion—laws that
describe and predict the motion of all objects on Earth. Newton
also wrote about the behavior of light, including how it can be
divided into colors by a glass prism.
1690 The clarinet, one example of sound energy being used to make
music, was invented in Germany.
1714 The mercury thermometer is introduced by Gabriel Fahrenheit.
Earlier thermometers, which used air instead of mercury, were
not as dependable since they were affected by atmospheric
changes. Atmospheric changes had no effect on the mercury
used to indicate temperature in Fahrenheit’s thermometer.
c. 1750Benjamin Franklin figures out that lightening is actually static
electricity. He also invents a very efficient stove for heating homes.
1769James Watt patents the first efficient steam engine.
1781The stagecoach carries passengers from place to place
throughout the world.
1787On the Delaware River, John Fitch makes the first successful
steamboat voyage.
1800sThe first iceboxes (the earliest “refrigerators”) are used in
homes. They are wooden boxes lined with tin or zinc and
insulated with materials such as cork, sawdust, and seaweed.
These early iceboxes are used to hold blocks of ice and “refrig-
erate” food. A drip pan underneath, which collects melted ice
water, has to be emptied daily.
1801Allesandro Volta creates the first electric battery.
Appendix A���
1821 Michael Faraday demonstrates that a moving magnet causes
electricity to flow through wires. This paves the way for the
electric motor and generator to be invented.
1827 The first photographic picture was produced by a French man
named Nicephore Niepce. He put a metal plate coated with
a special chemical into a camera box and took a picture—
exposing the plate to the sun’s energy (this took eight hours!).
When he washed it off he discovered that a permanent picture
remained.
English chemist John Walker invents the wooden match.
1830The first regular steam train passenger service starts.
1836In America, Samuel F. B. Morse sends messages over wires with
the first telegraph.
1843James Prescott Joule conducts a series of experiments to dem-
onstrate the law of conservation of energy: energy can neither
be created out of nothing nor destroyed into nothing, but
can be changed from one form to another.
���A Walk Through Energy History
1821 Michael Faraday demonstrates that a moving magnet causes
electricity to flow through wires. This paves the way for the
electric motor and generator to be invented.
1827 The first photographic picture was produced by a French man
named Nicephore Niepce. He put a metal plate coated with
a special chemical into a camera box and took a picture—
exposing the plate to the sun’s energy (this took eight hours!).
When he washed it off he discovered that a permanent picture
remained.
English chemist John Walker invents the wooden match.
1830The first regular steam train passenger service starts.
1836In America, Samuel F. B. Morse sends messages over wires with
the first telegraph.
1843James Prescott Joule conducts a series of experiments to dem-
onstrate the law of conservation of energy: energy can neither
be created out of nothing nor destroyed into nothing, but
can be changed from one form to another.
Appendix A���
1845 The rubber band is patented by Stephen Perry of London.
1859 Edwin L. Drake strikes oil at his homemade drilling rig in Titus-
ville, Pennsylvania. This is the first oil well in the United States.
It marks the beginning of the modern oil industry, which now
fuels the transportation and energy needs of the world.
1860s The booming steel industry greatly increases the demand
for coal.
1863 In the city of London, the first subway is built.
1865 James Clark Maxwell presents his electromagnetic theory,
which other inventors use to invent electric power, radios,
and television.
1876 Alexander Graham Bell invents the telephone.
1877 Thomas Edison invents the phonograph.
1879Thomas Edison patents an incandescent light bulb.
1880Wabash, Indiana becomes the first town completely illumi-
nated by electric lighting.
1882The world’s first hydroelectric plant opens in Appleton,
Wisconsin, demonstrating that moving water can generate
electricity.
1884The “Rover” bicycle, the first to have all the major features of
today’s bicycles, is introduced in Great Britain.
The first long-distance telephone call is made between Boston
and New York City.
1885Gottlieb Daimler and Karl Benz of Germany invent gasoline
engines similar to those still used in cars today.
1895Wilhelm Roentgen x-rays his wife’s hand to produce the first
“x-ray picture.”
Guglielmo Marconi sends and receives the first radio signal,
which leads to the invention of the radio.
���A Walk Through Energy History
1845 The rubber band is patented by Stephen Perry of London.
1859 Edwin L. Drake strikes oil at his homemade drilling rig in Titus-
ville, Pennsylvania. This is the first oil well in the United States.
It marks the beginning of the modern oil industry, which now
fuels the transportation and energy needs of the world.
1860s The booming steel industry greatly increases the demand
for coal.
1863 In the city of London, the first subway is built.
1865 James Clark Maxwell presents his electromagnetic theory,
which other inventors use to invent electric power, radios,
and television.
1876 Alexander Graham Bell invents the telephone.
1877 Thomas Edison invents the phonograph.
1879Thomas Edison patents an incandescent light bulb.
1880Wabash, Indiana becomes the first town completely illumi-
nated by electric lighting.
1882The world’s first hydroelectric plant opens in Appleton,
Wisconsin, demonstrating that moving water can generate
electricity.
1884The “Rover” bicycle, the first to have all the major features of
today’s bicycles, is introduced in Great Britain.
The first long-distance telephone call is made between Boston
and New York City.
1885Gottlieb Daimler and Karl Benz of Germany invent gasoline
engines similar to those still used in cars today.
1895Wilhelm Roentgen x-rays his wife’s hand to produce the first
“x-ray picture.”
Guglielmo Marconi sends and receives the first radio signal,
which leads to the invention of the radio.
Appendix A��0
1902 Willis Carrier builds the first air conditioner.
1903 The Wright Brothers fly the first engine-powered airplane near
Kitty Hawk, North Carolina. Their machine flies for 59 seconds,
and reaches an altitude (height) of 852 feet.
1905 Einstein links mass with energy through his famous formula
E=mc2.
This theory eventually led to nuclear power, nuclear weapons,
nuclear medicine, and the field of astrophysics.
The first “portable” electric vacuum cleaner is produced. It
weighs 92 pounds!
The first electric washing machine is sold.
1910Thomas Edison demonstrates “talking” pictures—the first
movies with sound “blended” in.
The first flight powered by a jet engine takes place over Paris,
France.
1911Marie Curie wins the Nobel Prize in Chemistry for her work
isolating radium, a substance which gives off radioactive
energy. Years later, radium is used to treat cancer.
1913The first “non-icebox” refrigerators (made with compressors)
for home use are manufactured in Chicago.
���A Walk Through Energy History
1902 Willis Carrier builds the first air conditioner.
1903 The Wright Brothers fly the first engine-powered airplane near
Kitty Hawk, North Carolina. Their machine flies for 59 seconds,
and reaches an altitude (height) of 852 feet.
1905 Einstein links mass with energy through his famous formula
E=mc2.
This theory eventually led to nuclear power, nuclear weapons,
nuclear medicine, and the field of astrophysics.
The first “portable” electric vacuum cleaner is produced. It
weighs 92 pounds!
The first electric washing machine is sold.
1910Thomas Edison demonstrates “talking” pictures—the first
movies with sound “blended” in.
The first flight powered by a jet engine takes place over Paris,
France.
1911Marie Curie wins the Nobel Prize in Chemistry for her work
isolating radium, a substance which gives off radioactive
energy. Years later, radium is used to treat cancer.
1913The first “non-icebox” refrigerators (made with compressors)
for home use are manufactured in Chicago.
Appendix A���
Henry Ford thinks of a way for workers to use a conveyor belt
to speed up production of the Model T Ford. Soon most manu-
facturers use this method to make large quantities of their
products, including cars.
1919 The modern pop-up toaster, which uses a timer to toast bread
to the desired doneness, is introduced by Charles Strite.
1926 First liquid-fuel rocket is launched by Robert Goddard.
1927 Philo T. Farnsworth successfully transmits a television signal.
The picture on the television screen is black and white.
1935 Major league baseball games are played at night for the first
time. Night games are made possible by electric lighting.
1936 The Hoover (Boulder) Dam is completed.
1938 The first color television is demonstrated in London.
1940A helicopter is invented by Igor Sikorsky—more than 400 years
after Leonardo da Vinci first describes this invention.
1942Scientists demonstrate the first controlled production of
nuclear energy.
1945The first atomic bomb is tested.
1947The microwave oven, invented by Percy Spencer, is introduced
by Raytheon Corporation.
1952The United States explodes the first hydrogen bomb.
1954Scientists show that the sun’s energy can be converted to elec-
tric current using silicon solar collectors.
The United States launches the USS Nautilus—the world’s first
nuclear-powered submarine.
1957The first commercial nuclear power plant begins operating in
Shippingport, Pennsylvania.
���A Walk Through Energy History
Henry Ford thinks of a way for workers to use a conveyor belt
to speed up production of the Model T Ford. Soon most manu-
facturers use this method to make large quantities of their
products, including cars.
1919 The modern pop-up toaster, which uses a timer to toast bread
to the desired doneness, is introduced by Charles Strite.
1926 First liquid-fuel rocket is launched by Robert Goddard.
1927 Philo T. Farnsworth successfully transmits a television signal.
The picture on the television screen is black and white.
1935 Major league baseball games are played at night for the first
time. Night games are made possible by electric lighting.
1936 The Hoover (Boulder) Dam is completed.
1938 The first color television is demonstrated in London.
1940A helicopter is invented by Igor Sikorsky—more than 400 years
after Leonardo da Vinci first describes this invention.
1942Scientists demonstrate the first controlled production of
nuclear energy.
1945The first atomic bomb is tested.
1947The microwave oven, invented by Percy Spencer, is introduced
by Raytheon Corporation.
1952The United States explodes the first hydrogen bomb.
1954Scientists show that the sun’s energy can be converted to elec-
tric current using silicon solar collectors.
The United States launches the USS Nautilus—the world’s first
nuclear-powered submarine.
1957The first commercial nuclear power plant begins operating in
Shippingport, Pennsylvania.
Appendix A���
1958 Scientists at AT&T Bell Laboratories invent the laser.
1963 The Clean Air Act is passed to protect Americans from harmful
air pollutants, such as those released by coal power plants and
steel mills.
1966 The first hand-held pocket calculator is invented.
1974 University City, Missouri is the first city to pick up recycling
from homes (newspapers only).
1976Edward Hammer presents an idea for a fluorescent “spiral
lamp.” Because of its high cost, compact fluorescent light
bulbs do not appear in stores until 1995.
1977The first cell phones are tried out in Chicago by two thousand
customers.
1978Texas Instruments patents the microchip for use in computers.
1980sThe first wind farms are built in the United States, providing
an alternative to power plants that burn fossil fuels.
���A Walk Through Energy History
1958 Scientists at AT&T Bell Laboratories invent the laser.
1963 The Clean Air Act is passed to protect Americans from harmful
air pollutants, such as those released by coal power plants and
steel mills.
1966 The first hand-held pocket calculator is invented.
1974 University City, Missouri is the first city to pick up recycling
from homes (newspapers only).
1976Edward Hammer presents an idea for a fluorescent “spiral
lamp.” Because of its high cost, compact fluorescent light
bulbs do not appear in stores until 1995.
1977The first cell phones are tried out in Chicago by two thousand
customers.
1978Texas Instruments patents the microchip for use in computers.
1980sThe first wind farms are built in the United States, providing
an alternative to power plants that burn fossil fuels.
Appendix A���
1982 The compact disc is available in stores.
1984 The first modern tidal power plant in North America opens
in Nova Scotia, demonstrating that the motion energy of the
tides can be used to generate electricity.
2004 Hybrid electric cars become widely available at car dealerships.