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Science Course Module: Integrated Physics and Chemistry (IPC) 2005 1

WAVES UNIT Catch a Wave!


UNIT INTRODUCTION

The study of waves is an important topic in science. Without waves, sounds would not be produced and heard by others. In this module, IPC students build a musical instrument. Each student demonstrates that his/her musical instrument can change pitch and plays a designated song with at least 8 different notes. Each student demonstrates to other fellow students that his/her musical instrument is "on pitch" by playing a set of 8 musical notes in order from lowest to highest pitch. IPC students study properties of waves, such as frequency, amplitude, wavelength, and types of waves. They examine how the pitch of a sound depends on the vibrating object's length, thickness and tightness. Student explorations include the use of a slinky to study longitudinal waves and the application of their knowledge to how sound travels through matter. Other explorations allow the student to observe how the pitch of different objects change, when set into vibration.

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TABLE OF CONTENTS

UNIT COMPONENTS PAGE

Steve’s Engaging Movie Clip A brief description of the accompanying SCIENCE in the MOVIES DVD for this unit.

Overview of Learning Experiences Targeted Science TEKS, Engage, Explore, Explain, Elaborate, Evaluate

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Unit Project Description An exciting project focuses student learning and participation in unit activities. A description of the project is outlined here.

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Unit Engagement Students participate in introductory activities to capture their interest about a problem or phenomenon and make connections to prior knowledge and experiences.

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Unit Exploration Students manipulate materials during hands-on activities to explore the concept further while sharing their observations and ideas with others.

Unit Explanation Students communicate their findings from the explore activity as the teacher guides the discussion using effective questioning strategies, introducing new terms as appropriate, and clarifying any misunderstandings.

Unit Elaboration Students apply, extend, and enhance their understanding by participating in additional active learning opportunities.

Unit Evaluation Students demonstrate their understanding of concepts. This section includes both a performance rubric and sample TAKS items.

Unit Materials List and description of items required for each section of the learning experience.

Background Information for Teachers Teaching tips/Common misconceptions.

References List of books, articles, and websites used by developers of this learning experience.

Master Copies Student sheets and other material to be copied by teacher when using these learning experiences in the classroom.

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Overview of Learning Experiences TEK

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5. Science concepts. The student knows how waves and sound are a part of everyday life. The student is expected to:

5A demonstrate wave types and their characteristics through a variety of activities such as modeling with ropes and coils, activating tuning forks, and interpreting data on seismic waves. 5B demonstrate wave interactions including interference, polarization, reflection, refraction and resonance within various materials. 5D demonstrate the application of acoustic principles such as in echolocation, musical instruments, noise pollution and sonograms.

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See Steve's "Catch A Wave" engaging movie clip Hit a tuning fork with a rubber mallet and put the vibrating ends into a glass of water. Discuss what happened and why.

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EXPLORATION ACTIVITIES: Exploration Activity One: “Pitch of a Sound” Exploration Activity Two: “Comparing and Contrasting Waves” Exploration Activity Three: “Station Lab for Sound Activities” Exploration Activity Four: “Building a Musical Instrument Project”

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WHOLE GROUP DISCUSSION Teacher facilitates a class discussion of findings and new understandings that resulted from the exploration activities. Students explain what they have learned.

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TECHNOLOGY CONNECTIONS Students surf the web for information on noise pollution, use of sound waves in sonograms, seismic waves caused by earthquakes, Tacoma-Narrows Bridge collapse, and how to build different musical instruments.

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FINAL PROJECT: “Build a Musical Instrument” Students design, construct and play a musical instrument for the class. They explore the need to discover how to make their instrument change pitch, and how to "tune" their instrument. They practice playing an eight note scale and find the music for another song to play for the class. The experiences in this unit are designed to ensure that students are successful in producing a musical instrument that can perform the required notes and song.

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Musical Instrument Project PROJECT DESCRIPTON: Every student designs and builds a musical instrument that can play a series of 8 notes of increasing pitch (suggestion: C,D,E,F,G,A,B,C) and will play the notes for the class. The student plays a designated song for the class that uses as many of the notes as possible. Each student will describe how to change the pitch of his/her musical instrument and how to change the loudness (amplitude) of the instrument. Students will apply what they have learned about the properties of sound and acoustics as they build and play their instruments.

ACTION: Students are hired to play background music for a movie using home-made instruments.

Design Constraints Materials: Students will build their instruments with inexpensive materials such as fishing line and plastic tubes. Teacher should supply books on musical instruments from a library and provide the opportunity for students to conduct Internet searches for ideas on building musical instruments. Students cannot use parts from other musical instruments and the instrument must play 8 notes of increasing pitch (suggested scale: C,D,E,F,G,A,B.C) If possible, the purchase of materials with school budget funds would help students with limited access to supplies for this project. Procedure and Analysis:

Musical Instrument Project Instruction Sheet given to students: You are in charge of designing and constructing your own musical instrument. You can get help from family members especially if a tool, such as a saw is needed. 1. The instrument must be a string, percussion or wind instrument. 2. The instrument cannot use parts from other musical instruments. 3. If you play a musical instrument, pick another type of instrument to construct for this project. 4. You must play a scale of eight notes in increasing pitch with your instrument: C,D,E,F,G,A,B,C on pitch. 5. You must play a song that uses at least six different musical notes. 6. Prepare a short oral presentation to the class, explaining how you built your instrument, how your instrument works to change loudness and pitch, and the problems you encountered while building and tuning the musical instrument. You must also tell the class where you found the idea for your instrument (book name and author or web page).

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WAVES UNIT Catch a Wave!7. On a poster or with a computer slide show, include diagrams of how you built your instrument, photos of the project from beginning to end and any other information that would make your presentation interesting to your fellow students and teacher.

DIRECTOR’S (Teacher) NOTES: 1. This project should take about three weeks. 2. Allow students to research ideas for their instruments using library books and the Internet. 3. Plan a firm date when their ideas are due to you for approval. 4. At the end of the first week of the project, students must bring in their instrument to show the progress of the project. 5. Set a due date for the instrument and posters or computer slide shows. 6. PVC pipe and bamboo make great wind instruments, such as pan pipes and flutes. 7. Fishing line can be used to make string instruments. A note of caution: Fishing line tends to stretch so students must be able to tighten or loosen the strings on the day of the presentation to tune their instruments. 8. Rubber sheeting, metal pipe, PVC pipe and copper tubing can be used to make percussion instruments such as xylophones and drums. 9. Local stores may be willing to donate small pieces of wood and other materials for the students to use. 10.After all instruments have been presented, a great idea is to videotape the entire class playing the required song. Showing the videotape is funny and enjoyable to everyone. 11. Encourage students to play other songs in addition to the required song. 12. Some students may wish to build an additional musical instrument. 13. Family members should receive clear instructions that if they help their children, the student must be actively involved in the building of the instrument. Stress that the "look of the instrument" is not important. Students must understand how their instrument works and must play the required song as close as possible "on pitch." Adults must supervise cutting, drilling, and all activities where safe practices must be used. 14. For students with little family support in this project, work days could be set up at school.

Once more for safety: Use protective eye wear if students are cutting materials for their projects. Adults must help with any tools used especially saws and drills. The project belongs to the student, but supervision is essential.

Cut, Print, and Wrap: Students use this checklist to make sure their presentations are complete: 1. The musical instrument is shown to the class. 2. You play at least a scale of eight notes on your instrument (C,D,E,F,G,A,B,C) 3. You play a song that uses at least six different notes. 4. Your musical notes were pretty close to correct pitch. 5. During your oral presentation, you explain how you built your musical instrument. 6. During your oral presentation, you explain how you change the instrument's pitch and loudness. 7. You explain any problems that you encountered during the design, construction, and tuning of the instrument. You include how you solved each problem. 8. Your poster or computer slide show includes diagrams of construction, photos of the project during construction, and any other interesting information that you can find about your instrument. 9. You play a more difficult song in addition to the required song. 10. You build and play more than one instrument.

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SHOW STEVE’S Catch a Wave CLIP to engage students in the study of Waves.

1. Hit a tuning fork with a rubber mallet and put the ends of the tuning fork in a glass of water. Discuss what happens and why.

2. Encourage students who play musical instruments to bring them in for a short demonstration. Let them play a song and explain how they change the pitch and loudness of their instrument.

3. Show objects that make different sounds and investigate why their pitch and loudness are different.

4. Discuss the change in a boy's voice as he grows up and apply it to the concepts of pitch change.

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Students explore the concept of waves and sounds and participate in four activities in which investigate these concepts.

Students engage in the following four inquiry-based activities:

Exploration Activity One: “Pitch of a Sound”

Students investigate sound waves and learn that the pitch of a wave is directly related to the frequency. They apply their knowledge by building a simple musical instrument. (This is not the Musical Instrument Project.) Exploration Activity Two: "Comparing and Contrasting Waves” Students investigate transverse and longitudinal waves and compare and contrast their properties. Exploration Activity Three: "Surfing Sound Stations” Students investigate sound energy and learn that sound is caused by vibrations. Further, they observe factors that affect sound, such as resonance, frequency, pitch, state of matter of the medium, and the thickness, length and tightness of the medium. Exploration Activity Four: "Building a Musical Instrument Project" Every student designs and builds a musical instrument that can play a series of 8 notes of increasing pitch (suggestion: C,D,E,F,G,A,B,C) and will play the notes for the class. The student plays a designated song for the class that uses as many of the notes as possible. Each student will describe how to change the pitch of his/her musical instrument and how to change the loudness (amplitude) of the instrument. Students will apply what they have learned about the properties of sound and acoustics as they build and play their instruments.

Throughout the unit, the central questions are:

1. How are changes in frequency, pitch, and loudness produced by different objects?

2. What are the properties of sound waves that have

been observed in each exploration?

Strategies:

The expectation is that students will be asking many questions, because they need information to successfully complete this project. Asking the same questions about different musical instruments yield answers that follow a common pattern. For example, students will come to realize that the length and thickness of a vibrating object affects the pitch of the sound it produces. They will also realize that the tightness of a string is related to the pitch of the note it produces.

Explore

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Pitch of a Sound Type of Lesson: Content with Process: Focus on constructing knowledge through active learning.

Learning Goal: Students investigate sound waves and learn that the pitch of a wave is directly related to the

frequency. They apply their knowledge by building a simple musical instrument. (This is not the Musical Instrument Project.)

Key Question: 1. If all sounds are caused by vibration, why are all sounds not exactly the same? 2. Why are some sounds high pitch, like a flute, and some sounds are low pitch , like a

tuba? IPC Content TEKS: 5) The student

knows the effects of waves on everyday life.

The student is expected to:

A) demonstrate wave types and their characteristics through a variety of activities such as modeling with ropes and coils, activating tuning forks, and interpreting data on seismic waves.

D) demonstrate the application of acoustic principles, such as in echolocation, musical instruments, noise pollution, and sonograms.

Related Process TEKS:

(1) Scientific processes. The student, for at least 40% of instructional time, conducts field and laboratory investigations using safe, environmentally appropriate, and ethical practices

The student is expected to: (A) demonstrate safe practices during field and laboratory investigations; and (B) make wise choices in the use and conservation of resources and the disposal or recycling of materials.

(2) Scientific

processes. The student uses scientific methods during field and laboratory investigations.

The student is expected to: (A) plan and implement experimental procedures including asking questions, formulating testable hypotheses, and selecting equipment and technology;

(B) collect data and make measurements with precision;

(C) organize, analyze, evaluate, make inferences, and predict trends from data; and

(D) communicate valid conclusions.

(3) Scientific

processes. The student uses critical thinking and scientific problem solving to make informed

The student is expected to: (A) analyze, review, and critique scientific explanations, including hypotheses and theories, as to their strengths and weaknesses using scientific evidence and information;

(B) draw inferences based on data related to promotional materials for

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WAVES UNIT Catch a Wave!decisions. products and services;

(C) evaluate the impact of research on scientific thought, society, and the environment;

(D) describe connections between physics and chemistry and future careers; and

(E) research and describe the history of physics, chemistry, and contributions of scientists.

To the Teacher: Sound depends on three factors: a vibrating source to create the sound waves, a medium (such as air) to carry the waves, and a receiver to hear them. Sound waves can't travel through a vacuum since there are no molecules to vibrate. Frequency is the number of vibrations or waves per unit time that pass a certain point. For a sound wave, it is the number of compressions that impact a given point during a second. Objects that vibrate rapidly produce many more compressions and refractions per second than objects that vibrate at a slower rate. Every cycle of sound has one compression (a region of increased pressure) and one rarefaction (a region where pressure is less than normal). The frequency of a sound wave is measured in hertz. Hertz (Hz) indicate the number of cycles per second that pass a given location. If a speaker's diaphragm is vibrating back and forth at a frequency of 900 Hz, then 900 compressions are generated every second, each followed by a rarefaction. This forms a sound wave whose frequency is 900 Hz. How the brain interprets the frequency of an emitted sound is called the pitch. We already know that the number of sound waves passing a point per second is the frequency. The faster the vibrations the emitted sound makes (or the higher the frequency), the higher the pitch. Therefore, when the frequency is low, the sound's pitch is lower. The pitch of sound (how high the note is) depends on the frequency of the wave. The higher the frequency, the higher the pitch. There are two ways to alter the pitch of a sound made by a string or a pipe. The longer the tube or string, the lower the pitch. The shorter the tube or string, the higher the pitch. See the "Catch The Waves" Master Template for more information on why the length affects the pitch.

LOW FREQUENCY LONGITUDINAL WAVE

HIGH FREQUENCY LONGITUDINAL WAVE

Logical-Mathematical Intelligence—

Consists of the ability to detect patterns, reason deductively and think logically. This intelligence is most often associated with scientific and mathematical thinking.

Multiple Intelligences:

Musical Encompasses the capability to recognize and compose musical pitches, tones,

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WAVES UNIT Catch a Wave!Intelligence—

and rhythms. (Auditory functions are required for a person to develop this intelligence in relation to pitch and tone, but it is not needed for the knowledge of rhythm.)

Materials:

• A corrugated plastic tube • Tuning forks • Small pieces of paper • Four straws • Scissors • Tape • Ruler • Three identical bottles • Wood ruler • Water • Rubber mallet or bottom of students' shoes (rubber soles are best)

SAFETY NOTE: Be careful to use a rubber mallet or the side of students' shoes to strike the tuning forks. Hitting the table top can cause damage to the surface of the tables and desks. Clear space around where the corrugated tube will swing so that students are not hit. Empty clear plastic water bottles work well for this activity. Glass bottles can

easily break. See Texas Science Safety Manual for lab and investigation guidelines: http://www.tenet.edu/teks/science/safety/safety_manual.html

Engagement: Ask students to strike a tuning fork on the side of their rubber soled shoes (or hit with a rubber mallet) and place it two inches away from their ear. Ask students to explain how they think the sound is being generated.

Hold the corrugated plastic tube in one hand at one end and swing it above your head, first slowly and then faster. Ask students to observe and take notes in their journal. Then tear a piece of paper into small pieces and leave them in a heap on the edge of the table. Hold with one hand the stationary end of the tube above the paper and with the other hand swing the tube.

When the tuning fork is at rest, the fork is surrounded by molecules in the air.

As a tuning fork's prongs move apart because of a vibration, the molecules ahead of it are crowded together. They look like they are being pushed together. They bump each other.

As a tuning fork vibrates, it causes molecules in the air to move. The molecules bump into other molecules nearby, causing them to move. This process continues from molecule to molecule. The result is a series of compressions and rarefactions that make up sound waves.

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WAVES UNIT Catch a Wave!Ask students to answer the following questions and have a classroom discussion:

1. What effect does the speed of the plastic tube have on how high or low (pitch) the sound is? The faster the tube is swung the higher the pitch of the sound.

2. What made the sound? The tube caused air molecules to vibrate and that caused the sound.

3. What effect did the swinging of the tube have on the papers on the desk? The air moving through the tube made the papers move and vibrate.

Explore:

1. Look at the diagram below. Take three out of the four straws and cut them so that you end up with seven straws of different length. (Do not cut one straw).

2. Measure and record the lengths of each straw on your lab paper. 3. Flatten one end of each straw. Use scissors to cut a small triangular piece off each of the two corners of the flattened

end of the straw. The cuts should produce reed-like mouthpieces on all eight straws. 4. Chew down on the mouth piece end of your straw to flatten it. If chewing or cutting has closed the trimmed end,

open it. 5. Place the trimmed end in your mouth and blow lightly. The end should be far enough in your mouth that the flaps are

free to vibrate. 6. Order them from longest to shortest and place tape across them so there is a gap between the straws. Place tape on

the other side so the straws are secure. 7. Blow across the tops of the straws. Listen carefully to the sounds. 8. Compare pitches of the notes produced by the straws of different length. 9. Another option is to do this activity but not worry about the reed-like mouthpieces. Blowing across the straws will

produce sounds of different frequencies.

Explain: Facilitation Questions:

1. Which length of straw produced the highest pitch sound? The shortest straw.

2. Which length of straw produced the lowest pitch sound? The longest straw.

3. Why do you think this happens? By increasing the length of the straw the air has a longer distance to travel, thus producing a lower sound.

Elaborate: 1. Fill three bottles with different amounts of water. 2. Predict which bottle will give the highest tone when struck on the side with a ruler. 3. Which bottle produces the highest pitch? 4. What was vibrating when the bottles were hit on the sides? 5. Blow over the mouths of the bottles and listen to the pitch of the sound produced. 6. What started vibrating when the bottles were blown into? 7. What is affecting the pitch of the sound? Another idea is to use a "Space Phone." This is marketed by various science supply companies. It is a long coil with a small megaphone on each end. By sending a compression through the coil, the megaphone amplifies the sound and makes unusual sounds. The sounds will remind the students of science fiction movie sounds. Study wind-chimes and determine how the pitch is changed. Students who play an instrument could bring in their instruments and show the class how they change the pitch.

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Evaluate

POINTS Scientific Accuracy

Reasoning Communication Collaboration

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I can accurately demonstrate all wave types and their characteristics through modeling.

I analyzed data accurately and answered the all the analysis questions accurately.

I communicated answers to the investigation questions completely and thoroughly using correct grammar. I shared my ideas about the investigation in the whole group discussion and with my team mates.

I worked extremely well with my group. Each person had a lot of input and participated in the investigation.

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I can demonstrate all wave types and their characteristics through modeling.

I analyzed data somewhat accurately and answered most of the analysis questions accurately.

I communicated answers to the investigation questions thoroughly using correct grammar. I shared my ideas about the investigation in the whole group discussion and with my team mates.

I worked well with my group. Each person had some input and participated in the investigation.

2

I can demonstrate some wave types and their characteristics through modeling.

I analyzed data and answered only a few of the analysis questions accurately.

I communicated answers to the investigation questions using correct grammar. I shared some of my ideas about the investigation in the whole group discussion and with my team mates.

I worked with my group. Some people did not have input and participated in the investigation.

1

I can not demonstrate wave types and their characteristics through modeling.

I did not analyzed data accurately and did not answer the analysis questions.

I did not communicate answers to the investigation questions using correct grammar. I did not share my ideas about the investigation in the whole group discussion and with my team mates.

I did not work well with my group. Few had input and participated in the investigation.

Subtotal: ____ Subtotal: ____ Subtotal: ____ Subtotal: ____

TOTAL: ____/16pts

References/Resources/Websites:

• Interactive Sound animations: http://library.thinkquest.org/19537/?tqskip1=1 http://library.thinkquest.org/19537/?tqskip1=1 • The Physics Classroom: http://www.glenbrook.k12.il.us/gbssci/phys/Class/BBoard.html

The following sites contain information about one or more of these topics: waves, sound, light and musical instruments:

• http://www.42explore.com/musicmnts.htm • http://midwestworldfest.org/japan/frames/2_b_instrum.html • http://www.sciencenews.org/articles/20040306/bob8.asp (Killer Waves: Scientists are learning to predict tsunami risk) • http://www.soc.soton.ac.uk/JRD/SCHOOL/eq/eq001a_wave01.html (Information about all types of waves and their characteristics from the Southampton Oceanography Centre) • http://www.sciencetech.technomuses.ca/english/schoolzone/Info_Sound.cfm • http://www.gmi.edu/~drussell/Demos/waves/wavemotion.html

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WAVES UNIT Catch a Wave!(Kettering University wave animation) • http://www.sciencemadesimple.com/index.html (This site has free information. It is not necessary to subscribe)

This site has teacher lesson plans for sound: • http://school.discovery.com/lessonplans/programs/soundwaves/

These sites have information about I.P.C. including this unit: • http://www.colorado.edu/physics/2000/waves_particles/wavpart3.html • http://www.sciencenews.org/ (This site does have advertisements) • http://www.school-for-champions.com/science.htm • http://www.thinkquest.org/library/cat_show.html?cat_id=36 • http://www.physicsclassroom.com/ • http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html • http://www.sciencespot.net/Pages/kdzphysics3.html • http://school.discovery.com/lessonplans/physci.html (teacher lessons)

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Comparing and Contrasting Waves

Type of Lesson:

1. Content with Process: Focus on constructing knowledge though active learning.

IPC Content TEKS:

5A 5B

Students investigate and demonstrate wave types and their characteristics. Students demonstrate wave interactions including interference, reflection, refraction and resonance within various materials

Learning Goal/ Instructional Goal:

Learning Goal: Students investigate transverse and longitudinal waves and compare and contrast their properties. Instructional Objectives While participating in this exploration, students will be able to 1. Explain how a longitudinal wave is produced on a drawing and label compressions and rarefactions. 2. Explain how a transverse wave is produced and on a drawing can label the crest, trough, amplitude, frequency and wavelength. 3. Produce constructive and destructive interference with pulses on a slinky and explain how interference affect the waves observed. 4. Create standing waves and show how waves of different frequencies are produced.

Key Question:

How does the energy of a wave affect the characteristics of a wave?


(1) Scientific processes. The student, for at least 40% of instructional time, conducts field and laboratory investigations using safe, environmentally appropriate, and ethical practices


(2) Scientific

processes. The student uses scientific methods during field and laboratory investigations.




(D) communicate valid conclusions. (3) Scientific

processes. The student uses critical thinking and scientific problem solving to make informed decisions.


(B) draw inferences based on data related to promotional materials for products and services;

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WAVES UNIT Catch a Wave!(C) evaluate the impact of research on scientific thought, society, and the environment;


(E) Research and describe the history of physics, chemistry, and contributions of scientists.

To the Teacher:

DO NOT OVERSTRETCH THE SLINKY! ONCE YOU HAVE THE SLINKY STRECHED OUT, DO NOT LET GO! THIS WILL DAMAGE THE SLINKY. Logical-Mathematical Intelligence—


Linguistic Intelligence—

Involves having a mastery of language. This intelligence includes the ability to effectively manipulate language to express oneself rhetorically or poetically. It also allows one to use language as a means to remember information.

Interpersonal Intelligence—

Includes interpersonal feelings and intentions of others.

Intrapersonal Intelligence—

Intrapersonal intelligence--the ability to understand one's own feelings and motivations.

Spatial Intelligence—

Gives one the ability to manipulate and create mental images in order to solve problems. This intelligence is not limited to visual domains--Gardner notes that spatial intelligence is also formed in blind children.

Musical Intelligence—

Encompasses the capability to recognize and compose musical pitches, tones, and rhythms. (Auditory functions are required for a person to develop this intelligence in relation to pitch and tone, but it is not needed for the knowledge of rhythm.)


Bodily-Kinesthetic Intelligence—

Is the ability to use one's mental abilities to coordinate one's own bodily movements. This intelligence challenges the popular belief that mental and physical activities are unrelated.

Materials:

• Large, metal slinky

SAFETY NOTE: DO NOT OVERSTRETCH THE SLINKY! ONCE YOU HAVE THE SLINKY STRECHED OUT, DO NOT LET GO! THIS WILL DAMAGE THE SLINKY AND COULD INJURE SOMEONE. See Texas Science Safety Manual for lab and investigation guidelines: http://www.tenet.edu/teks/science/safety/safety_manual.html Engagement:

1. Use a flat dish of water on a projector and drop a small pebble or object into the water. Discuss the types of waves produced. Put up barriers and show reflection of waves. This demonstration can also be used to illustrate diffraction and refraction of waves.

2. Ask students who have been on a small boat to explain what the waves going by look like and how they affect the boat. 3. Use a "Space Phone" sold by science catalog companies. Produce a transverse wave and then a longitudinal wave. (The

"Space Phone" is a long coil with small megaphones on each end. A longitudinal wave produces unusual sounds.) Discuss with the class the difference between transverse and longitudinal waves.

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WAVES UNIT Catch a Wave! Explore: TRANSVERSE WAVES A transverse wave is easy to see. To make one, practice moving your hand very quickly back and forth at right angles to the stretched spring until you can produce a pulse that travels down only one side of the spring. This pulse is called “transverse ” because the individual coils of wire move at right angles to (transverse to) the length of the spring.

1. Look at the wave generated by the slinky and draw what the wave looks like in your journal. Label the parts of the

wave accordingly (amplitude, wavelength, crest, and trough).

Analysis/Conclusions Questions:

2. Does the pulse reflected from the far end of the spring return to you on the same side of the spring as the original, or on the opposite side? Why?

3. It depends if someone is holding onto the other end of the spring. If there is no support on the opposite end to generate an equal but opposite force (Newton's Third Law) on this spring, the pulse will return on the same side. If there is someone holding the other end of the spring, the pulse will return to you on the opposite side because an equal but opposite force has been exerted.

4. What is an example of a transverse wave? Light travels as a transverse wave. LONGITUDINAL WAVES With a partner to help you, pull the spring out on a smooth floor to a length of about 6 to 10 meters. With your free hand, grasp the stretched spring about a meter from one end. Pull the meter of spring together toward yourself and then release it being careful not to let go of the fixed end with your other hand! Notice the single wave, called a pulse, travel along the spring. In such a longitudinal pulse, the spring coils move back and forth along the same direction as the wave travels. The wave carries energy, but the spring remains stationary after the pulse has passed through it and reflected from the other end. Note: You can see a longitudinal wave more easily if you tie pieces of string or put a paper clip on several of the loops of the spring and watch their motion when the spring is pulsed. Analysis/Conclusion Questions: Look at the second wave generated and draw what it looks like in your journal.

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2. What is an example of a longitudinal wave?

Sound travels as a longitudinal wave.

3. How are the transverse waves similar to the longitudinal? Both are examples of energy being transferred from one place to another.

4. How are the transverse waves different from the longitudinal? In a transverse wave, the wave moves up and down as it moves across. In a longitudinal wave, the compression moves back and forth in the same direction as the wave does.

CONSTRUCTIVE AND DESTRUCTIVE INTERFERENCE Have your partner send a transverse pulse on the same side at the same instant you do, so that the two pulses meet the middle of the spring. The interaction of the two pulses is called interference. Questions:

1. What happens when the two pulses reach the center of the spring? Describe the size, shape, speed and direction of each pulse during and after the interaction. It will be easier to see what happens in the interaction if one pulse is larger than the other.

Student answers will vary based on how they set up their pulses. 2. What happens when two pulses on opposite sides of the spring meet? That is, send one down the

right side and have your partner send another down the left side at the same time. Describe the size, shape, speed and direction of each pulse during and after the interaction. It will be easier to see what happens in the interaction if one pulse is larger than the other.

Student answers will vary based on how they set up their pulses. STANDING WAVES By vibrating your hand steadily back and forth, you can produce a train of pulses, or a periodic wave. The distance between any two neighboring crests on such a periodic wave is the wavelength. The rate at which you vibrate the spring will determine the frequency of the periodic wave. Produce various short bursts of periodic waves so that you can answer the following question. Question:

1. How does the wavelength depend on the frequency? As the wave crests get closer together (smaller wavelength), the frequency increases (more waves per second)

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WAVES UNIT Catch a Wave! Analysis and conclusions 1. By vibrating your hand steadily back and forth, you can produce a train of pulses, or a periodic wave. Try to create

and draw the following waves in your journal with the characteristics described:

• High amplitude-short wavelength • Low amplitude-short wavelength • High amplitude-long wavelength • Low amplitude- long wavelength

Label the parts of your transverse waves from the above question in each of the drawings.

• Crest • Trough • Wavelength • Amplitude

1. Look back at the waves that you created above. Which waves have a high frequency? The shorter the wavelength, the higher the frequency. The first two waves have a high frequency. 2. Which waves have a low frequency? The longer the wavelength, the lower the frequency. The last two waves have a low frequency. laborate:

1. Use an oscilloscope hooked up to a microphone to show different types of waves. 2. Research seismic waves and show the wave patterns.se large tuning forks that are attached to

resonance boxes and illustrate constructive interference, destructive interference (beats) and resonance (sympathetic vibrations) to show properties of sound waves.

5. Compare and contrast transverse waves (such as light energy) with longitudinal waves (such as sound) and discuss where each wave travels the fastest, slowest and cannot travel at all. Include in your discussion, their relative speeds. This is a good bridge into the study of light energy and electromagnetic waves.

6. Discuss standing waves in more detail. Evaluate: Students create a poster comparing and contrasting transverse and longitudinal waves in the following ways: 1. How does each wave travel? 2. What are examples of each type of wave? 3. Label the parts of each wave. 4. Explain how changing amplitude and frequency changes what you see of hear. 5. What mediums allow each wave to travel through easily? with difficulty? Why? 6. How can you use your knowledge of waves to build a musical instrument?

Sample Rubric:


Reasoning

Communication

Collaboration

4

All information given was accurate. I can demonstrate wave types and their characteristics accurately.

I made excellent conclusions and gave evidence to support my conclusions.

All team members took part in the presentation and spoke clearly. The presentation held the attention of the other students.

My team worked together in an organized manner and stayed on task.

3

Most information given was accurate. I can demonstrate wave types and their characteristics.

I made good conclusions and gave some good evidence to support my conclusions.

Most team members spoke and the presentation was fairly interesting.

My team worked fairly well together. Some members not always on task.

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2

Some information was accurate but there were some mistakes. I can identify some wave types and a few characteristics.

My conclusions made were weak and I had little supporting evidence.

Some team members spoke and presentation was hard to understand.

My team worked together but was disorganized. Members were sometimes off task.

1

Most information given was inaccurate and there were many mistakes. I can not identify wave types or characteristics of waves.

My conclusions were poor and I gave no evidence to support my conclusions.

A few students spoke but other team members did not participate. Presentation was difficult to understand.

My team worked very poorly together and members were often off task.

Subtotal: ____ Subtotal: ____ Subtotal: ____ Subtotal: ____ TOTAL: ____/16pts

References/Resources/Websites: • http://www.42explore.com/musicmnts.htm • http://midwestworldfest.org/japan/frames/2_b_instrum.html • http://www.sciencenews.org/articles/20040306/bob8.asp (Killer Waves: Scientists are learning to predict tsunami risk) • http://www.soc.soton.ac.uk/JRD/SCHOOL/eq/eq001a_wave01.html (Information about all types of waves and their

characteristics from the Southampton Oceanography Centre) • http://www.sciencetech.technomuses.ca/english/schoolzone/Info_Sound.cfm • http://www.glenbrook.k12.il.us/gbssci/phys/class/light/lighttoc.html (Physics Classroom) • http://www.gmi.edu/~drussell/Demos/waves/wavemotion.html (Kettering University wave animation) • http://www.sciencemadesimple.com/index.html (This site has free information. It is not necessary to subscribe)

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Lab-Sound Surfing for Sound Waves Stations Type of Lesson: Content with Process: Focus on constructing knowledge through active learning.

IPC Content TEKS: 5A

5B 5D

Demonstrate wave types and their characteristics through a variety of activities such as modeling with ropes and coils, activating tuning forks, and interpreting data on seismic waves. Demonstrate wave interactions including interference, polarization, reflection, refraction and resonance within various materials. Demonstrate the application of acoustic principles such as in echolocation, musical instruments, noise pollution and sonograms.

Learning Goal/ Instructional Objective:

Learning Goal: Students investigate sound energy and learn that sound is caused by vibrations. Further, they observe factors that affect sound, such as resonance, frequency, pitch, state of matter of the medium, and the thickness, length and tightness of the medium. Instructional Objectives: While conducting this exploration, students will be able to:

4. Explain that sound is made by the vibrations of molecules that travels as a longitudinal wave.

5. Observe that higher frequencies sound waves produce higher pitches. 6. Discuss that sound travels fastest in solids where the molecules are closer

together and more elastic, and slower through gases like air because the molecules are further apart and harder to vibrate quickly.

7. Recognize resonance when you set up vibrations at a certain frequency that matches another object's natural frequency. The second object begins to vibrate too.

8. Increase tightness of a string by tightening it. 9. Observe that as the length of a straw or string decreases, the sound's pitch

increases.

Key Questions: What are the properties of sound? How do you change the speed of sound? How can you change the pitch of a string or wind instrument?


(1) Scientific processes. The student, for at least 40% of instructional time, conducts field and laboratory investigations using safe, environmentally appropriate, and ethical practices.


(2) Scientific

processes. The student uses scientific methods during


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WAVES UNIT Catch a Wave!field and laboratory investigations.



(D) communicate valid conclusions.

(3) Scientific

processes. The student uses critical thinking and scientific problem solving to make informed decisions.


(B) draw inferences based on data related to promotional materials for products and services;

(C) evaluate the impact of research on scientific thought, society, and the environment;


(E) Research and describe the history of physics, chemistry, and contributions of scientists.

To the Teacher: 1. Sound is produced by the vibration of molecules. 2. Sound travels as a longitudinal wave. Moving back and forth in the same direction as the

wave. The rarefactions are areas of low pressure of molecules and compressions are areas of high pressure of molecules.

3. Sound travels fastest through solids because their molecules are close together. Elastic solids allow sound to travel quickly. Sound travels slowly through gases because their molecules are far apart and difficult to vibrate. Sound waves cannot travel at all through a vacuum because there are no molecules to vibrate.

4. As the amplitude of a sound changes, its loudness changes. The more energy that a wave has, the greater its amplitude and loudness.

5. The pitch (highness or lowness) of a sound depends on its frequency. The higher the frequency, the higher the pitch.

6. Every object has its own natural frequency. When you match the natural frequency of the object, it begins to vibrate and you hear resonance. (Also called sympathetic vibrations)

7. The thicker a string, the lower its pitch; the thinner the string, the higher its pitch. 8. As a string is tightened, its pitch increases because the string will vibrate faster. 9. Waves show the property of reflection when they hit a barrier and most of the energy

bounces back. The Law of Reflection can be shown with ripple tank waves because the angle that they hit the barrier (Angle of Incidence) equals the angle that they bounce off (Angle of Reflection). Refraction can be shown if the tank has different depths of water. Interference can be shown by the effect of two waves hitting each other.

Logical-Mathematical Intelligence


Linguistic Intelligence

Involves having a mastery of language. This intelligence includes the ability to effectively manipulate language to express oneself rhetorically or poetically. It also allows one to use language as a means to remember information.

Interpersonal Intelligence

Includes interpersonal feelings and intentions of others.


Intrapersonal Intelligence

Intrapersonal intelligence--the ability to understand one's own feelings and motivations.

Materials:

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WAVES UNIT Catch a Wave! SAFETY NOTE:

1. Students must put all materials back on the lab table before moving to the next station. This will prevent objects from falling off of the table as teams move around the room. 2. Some stations contain glass containers. Check the glass before starting the lab station. If there are any cracks, notify the teacher immediately.

3. Clean up any spills before moving to the next station. 4. See Texas Science Safety Manual for lab and investigation guidelines:

http://www.tenet.edu/teks/science/safety/safety_manual.html

Engagement: 1. Show a short movie clip from a science fiction movie like "Star Wars" where the battle scenes in the middle of space

have the sounds of explosions and engines noises. Ask the question: If this really happened in the middle of outer space where it is a vacuum, would what you are hearing be accurate?

2. Bring in several sized tuning forks and hit each one with a rubber mallet? Why do they sound different? 3. Play a guitar or child's xylophone for the class. Why does each note sound different? 4. Find examples of common household items that make different sounds. Discuss why the sounds are different.

Explore: Follow the procedures below. Procedure See Student Pages in the back of the unit for a list of procedures for each of the stations. You will find the questions and

possible answers to each. Some or all of the stations can be used in your classroom.

Explain: (Sample student answers in italics) Questions for Hang It Up Station

1. What do you hear with the ear in which the pencil is placed? I heard the sound of the objects hitting each other. 2. Why didn’t you hear the coat hanger vibrations through the air? Air does not conduct sound as easily as solids do.

3. What was the source of the sound? The vibrations were made when the hanger hit a solid object.

4. Describe how the vibrations reached your ear from the source? The molecules vibrated inside the hanger and the vibrations traveled quickly toward my ear because the molecules in solids are so close together.

5. What other objects could you hang from the string for a source of sound? Any solids that are elastic and whose molecules can vibrate easily when hit.

Questions for Ring Around the Rim Station

1. What is the purpose of the vinegar? The vinegar produces the right amount of friction needed to cause resonance in the glass of water.

2. Why do the hands and glass have to be cleaned? Dirt on my hands or on the glass prevents the friction needed to cause the resonance of the glass of water.

3. What is the finger actually doing when it rubs the glass rim? My finger is making vibrations. (Teacher note: This is similar to a bow rubbing on a string of a violin.)

4. What happens to the pitch when water is added to the glass? When the frequency of the vibrations that I make matches the natural frequency of the water and glass, a sound is made.

5. How does the pitch change as you add more water?

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WAVES UNIT Catch a Wave!The higher the water level, the lower the pitch is. When there is less water, the pitch is higher.

Questions for Phone Home Station

1. Are the vibrations generated longitudinal or transverse? All sounds are made by longitudinal waves traveling through the string. 2. Why does the cup appear to amplify the sound?

The cup vibrates the air molecules and this causes a louder sound.

3. Why does the sound travel better through the string than through the air? String molecules are closer together than air molecules. Longitudinal waves need molecules so that the compressions can travel back and forth

4. Could a whisper be heard from one end of the classroom to the other end through this telephone? Through the air? It would be easier for a whisper to be heard on a telephone because the waves are traveling through a solid. Air molecules are much further apart so sound waves have much more trouble traveling through it.

Questions for Tuning Out Station

1. Compare the sounds and frequencies of the two forks. Does there seem to be any relationship between the number on the side of the tuning fork, its sound and its frequency? If so, what is the relationship?

The smaller the tuning fork, the higher the pitch sounded and the frequency number on the side of the tuning fork was a higher number. As the tuning fork got longer, the pitch sounded lower and the frequency number was a lower number.

2. Were the sounds made by the tuning forks the result of vibrations? Explain.

The sounds were made by vibrations. I saw the water vibrate and splash out of the beaker when the tuning fork went into the water. Teacher note: A ping pong ball attached to a string and hung from a stand is very effective at showing the vibrations of the tuning forks. The ping pong ball swings back and forth when the ball is touched by the vibrating tuning fork. Questions for Rubber Band-jo station

1. What happens to the pitch as you widen the gap between your fingers? The pitch goes higher when the rubber band is stretched tighter. 2. What properties of the rubber band changed while being stretched? The tension (tightness) of the rubber band changed. As the rubber band tightened, it became easier for the vibrations to travel faster through the band.

3. How does the pitch change when a guitar string is tightened? When a guitar string is tightened, the pitch of the string goes up too. 4. Which rubber band produced the highest pitched sound? The lowest pitched sound? If all rubber bands were at the same tightness, the small, thinner rubber band had the highest pitch. The thicker rubber band had the lower pitch.

Questions for Amplifiers Lab Station 1. Which step produced the louder sound? Step #2 produced the louder sound. 2. How did the sound get amplified? The surface area of the table touching the air is greater than the comb. The comb causes the table's molecules to vibrate and the air molecules touched by the table begin to vibrate. This produce more vibrating molecules and a louder sound. 3. Was there a different sound produced with the other comb? Answers vary depending on the type of comb chosen. 4. What caused the change in pitch? Answers will vary but may include the thickness of the comb of the size of the comb.

5. Which material amplified the sound the greatest? Answers vary.

6. Explain how musical instruments can use amplifiers.

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WAVES UNIT Catch a Wave!Answers vary. For example: Guitars have resonance chambers. The more air molecules that can be set into motion, the louder the sound. Straw Oboe Lab Station Questions:

1. What is producing the sound? The air inside the straw is vibrating. 2. How did the pitch change when all of the holes were closed? How did that pitch compare to the sound that was heard when all of the holes were open? When all of the holes were closed, the pitch was lower. When the holes were open, the pitch was higher.

3. What does opening or closing a hole in the straw really mean in terms of vibrating an air column? When all of the holes were closed, the vibrating air column was longer and the pitch was lower. As the holes were opened, the shorter the vibrating air column and the higher the pitch. Teacher Note: When the holes were closed, the length of the tube is longer. That is, the standing wave length is longer. Since velocity equals the product of frequency times wavelength, and the velocity stays constant, the wavelength increases and the frequency decreases. This means that the pitch decreases (gets lower). this is also the reason why the pitch goes up as the straw is cut shorter.

4. What happens to the pitch as you cut off pieces of the straw? Why? As the straw was cut, the pitch increases as the vibrating column of air gets shorter.

Questions for Rocking Pebbles Station

1. Predict what will happen if you pluck the rubber band.

Answers will vary.

2. Predict what will happen to the pebbles if you pluck the rubber band.

Answers will vary.

3. What did you observe about the rubber band? Did it create a sound?

The rubber band makes a small sound.

4. What caused the sound?

As the rubber band vibrates, it makes sound waves and causes the pan to vibrate.

5. What did you observe about the pebbles? What caused their motion?

The pebbles started to vibrate because the rubber band vibrated the baking pan. The pebbles were easily moved by the vibrating pan as the energy was transferred.

Questions for Stringed Instrument Lab Station

1. What do you observe about the rubber bands? The rubber bands are the same thickness but different lengths.

2. Predict what sounds the different rubber bands will make when they are plucked. Answers will vary.

3. How do the sounds of the three rubber bands compare?

The shortest string had the highest pitch and the longest rubber band had the lowest pitch.

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4. Which string vibrates the quickest? Which string vibrates the slowest?

The short string vibrated the fastest and the long string vibrated the slowest.

5. What can you say about the speed of the vibrations and the sound that is produced?

The faster that the string vibrates, the higher the pitch of the string is.

6. How does the pitch differ as you change the length of the rubber band?

As I change the length of the rubber band and hold it down in the middle, the pitch goes up.

Questions for Vibrating Ruler Lab Station

1. What do you predict will happen to the pitch of the sound if we make the ruler longer? Answers will vary.

2. How does the sound compare to the first sound made by the ruler?

The pitch goes down because the ruler is longer and vibrated slower.

3. What happens to the pitch as the length of the ruler changes?

As the ruler sticking out over the table increases in length, the pitch decreases.

Questions for Tuned In Washers Lab Station

1. What washers started to swing when you swung washer number 7? Why?

The washer that hangs at the same length vibrated because it has the same natural frequency.

2. Predict which washer would swing with washer number 1.

Answers might vary.

3. Was your prediction accurate? Why or why not?

Answers might vary.

4. If washer number 2 were swinging first, what washer would swing with it?

The washer that hangs at the same length will swing because it has the same natural frequency.

5. How can we compare this event with a sound source and resonating objects?

If two objects have the same natural frequency, and one vibrates, the other will start to vibrate if it is free to do so. This is called resonance (sympathetic vibrations) and is seen with drum membranes that start to vibrate when music is played.

Teacher Note: Piano strings can begin to vibrate if a tuning fork with the same frequency as one of the strings begins to vibrate. Guitar strings and tuning forks mounted on resonance boxes can also vibrate at certain frequencies. Resonance caused the collapse of the Tacoma Narrows Bridge. It is also the reason why soldiers crossing a bridge that can swing, break step and do not march in unison. If they march in military fashion, they may match the bridge's natural frequency. If the bridge starts to swing, it might collapse. Finally, resonance can be used to break a glass when its natural frequency is matched by a singer.

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WAVES UNIT Catch a Wave!Questions for Dropping Sound Lab Station

1. Which object sent out the sound waves with the largest frequency (highest pitch)?

Answer may vary.

2. Which object sent out sound waves with the largest amplitude (loudest sound)?

Answers may vary.

Elaborate: 1. Discuss how information learned in this exploration could be used to pick and construct the students' musical instruments. 2. Investigate how musical instruments use resonance. 3. Investigate racing teams that are building cars that can go faster than the speed of sound. 4. Investigate aircraft that can go faster than Mach 1. 5. Investigate the uses of sound waves in medicine and technology. 6. Find other examples of movies (besides the "Star Wars" film mentioned at the beginning of this exploration) that mistakenly showed that sound can travel through a vacuum. 7. Compare the speed of sound to light as in the example of lightning and thunder. 8. Investigate the resonance examples listed in the Teacher's Note paragraph for the Washers Lab Station. Evaluate: Each team must demonstrate a property of sound that the team members find interesting. Use materials that have not been used. Demonstrate the property of sound using a visual poster, computer slide show or using actual materials. Share why you picked that property of sound and what is so interesting about it. Do research into properties of sound energy or interesting facts that we did not discuss. Each team will present to the class in an oral report lasting no more than five minutes. See rubric on the next page. Grading Rubric


Demonstration matched

property chosen

Communication and Collaboration

Effort and Interesting to class

4

Information presented was very accurate.

Information perfectly explained the property of sound chosen.

Team worked well together and presented information clearly.

Presentation showed lots of effort and was very interesting.

3

Information presented was mostly accurate.

Information mostly explained the property of sound chosen.

Team worked somewhat well together and presented information adequately.

Presentation showed average effort and was fairly interesting.

2

Information presented had some errors.

Information somewhat explained the property of sound chosen.

Team had problems working together and presentation was below average.

Presentation showed some effort and was not very interesting.

1

Information presented had many errors.

Information did not explain the property of sound chosen.

Team-work and presentation were poor.

Presentation showed little effort and was uninteresting.

Subtotal: ____ Subtotal: ____ Subtotal: ____ Subtotal: ____

TOTAL: ____/16pts

References/Resources/Websites:

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WAVES UNIT Catch a Wave!The following sites contain information about one or more of these topics: waves, sound, light and musical instruments:

• http://www.42explore.com/musicmnts.htm

• http://midwestworldfest.org/japan/frames/2_b_instrum.html

• http://www.sciencenews.org/articles/20040306/bob8.asp (Killer Waves: Scientists learning to predict tsunami risk)

• http://www.soc.soton.ac.uk/JRD/SCHOOL/eq/eq001a_wave01.html (Information about all types of waves and their characteristics from the Southampton Oceanography Centre)

• http://www.sciencetech.technomuses.ca/english/schoolzone/Info_Sound.cfm

• http://www.glenbrook.k12.il.us/gbssci/phys/class/light/lighttoc.html (Physics Classroom)

• http://www.gmi.edu/~drussell/Demos/waves/wavemotion.html (Kettering University wave animation)

• http://www.sciencemadesimple.com/index.html (This site has free information. It is not necessary to subscribe)

This site has teacher lesson plans for sound: • http://school.discovery.com/lessonplans/programs/soundwaves/

These sites have information about I.P.C. including this unit: • http://www.colorado.edu/physics/2000/waves_particles/wavpart3.html

• http://www.sciencenews.org/ (This site does have advertisements)

• http://www.school-for-champions.com/science.htm

• http://www.thinkquest.org/library/cat_show.html?cat_id=36

• http://www.physicsclassroom.com/

• http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

• http://www.sciencespot.net/Pages/kdzphysics3.html

• http://school.discovery.com/lessonplans/physci.html (teacher lessons)

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IPC: Science Course Module—Goes to the Movies!

Important Teacher Information

EE XXPP LL AA

II NN

Suggested Teaching Strategy: Whole Group Class Discussion Teacher facilitates a class discussion of findings and new understandings that resulted from the exploration activities. Students do the explaining.

How did you change the pitch of different musical instruments? Why did it change the pitch? As the length of a string, wind instrument or percussion instrument increases, the pitch decreases. As the thickness increases, the pitch decreases. As the tightness of a string increases, the pitch increases. This can be proved by a physics formula:

v2 = FT /(m/L) v = velocity of wave m= mass of string FT = tension on string L = length of string As the velocity of the wave changes, its frequency changes in direct proportion. The following explanation may be in more detail than your students want to know but it is excellent background information. The pitch of a sound depends on its frequency. Frequency is inversely proportional to the length of the string. The fundamental is the lowest resonant frequency when the nodes of the string vibrating only occur at the ends. The wavelength is equal to twice the length of the string. Frequency = velocity/ two times the length of the string. When you place your finger on the string, you shorten the wavelength of the fundamental and increase the pitch and fundamental frequency. Strings are different thickness, have a different mass per unit length. This affects the velocity. The velocity on a heavier string is less and so the frequency will be less for the same wavelength. Adjusting the tension affects the velocity of the wave. The velocity increases on a tighter string and the frequency and pitch also increase. The loudness of a string can be increased by plucking it with more force but a more effective way to increase loudness is by using a sounding box or board which can be set into vibration by the strings. This is a good example of resonance. A much larger surface area of air is in contact with the sounding box (board) and a louder sound is heard. Electric amplifiers can also be used. The air in the column of a wind instrument vibrates. A vibrating reed, the vibrating lips of the player or a stream of air directed against one side of the opening or mouthpiece can set the air into vibration. The frequencies that correspond to the standing waves are heard. The tube must be open at least on one end or no sound will be produced. The longer the length of the vibrating air column, the lower the frequency for reasons similar to a string. A percussion instrument can use open tubes or flat bars. The pitch also changes depending on the length of the vibrating material. The longer and wider the bar or tube, the lower the pitch is. In all cases loudness is related to the intensity of the wave. Intensity is defined as the energy transported and is proportional to the square of the wave amplitude. So the more energy given in striking the percussion instrument, plucking the string or blowing into the wind instrument, the louder the sound because the amplitude of the wave increases. An excellent reference for open and closed tube pitches, sonograms, and everything about sound is

Physics Principles With Applications by Douglas Giancoli 1998 ISBN 0-13-611971-9 Published by Prentice Hall

pages 347-381. This book was used as a reference for the information on this page.

Explain

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Students research and investigate everyday sound and wave issues via a variety of extension activities.

1. Discuss with students how they hear destructive and constructive interference when instruments are tuned.

2. Relate how resonance is essential to building musical instruments.

3. Research how sound waves are used in sonograms and other medical uses.

4. Measure sound levels using a sound meter and report on the effects of exposure to loud sounds over long periods of time. Research noise pollution effects.

5. Look at seismic waves from earthquakes and describe the different types of waves.

6. Vibrate two tuning forks with the same frequency to hear constructive interference. Vibrate two tuning forks with different frequencies to hear beats (destructive interference) and discuss how the wave patterns lead to what you hear.

7. Vibrate a tuning fork and see if you can vibrate the string on a guitar by using resonance (sympathetic vibrations). Research the collapse of the Tacoma-Narrows Bridge in the state of Washington and how it involved resonance.

8. Summarize the characteristics of mechanical sound waves when students begin to study the electromagnetic waves.

Elaborate

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Student understanding of sound and waves is evaluated using a performance rubric and by successfully responding to a set of selected response (TAKS-like) items.

The rubric for this project can be found on the next page. A sample student checklist can be used by the teacher and students to prepare for the final presentation:

1. The musical instrument is shown to the class.

2. You play eight musical notes in increasing pitch on the musical instrument. (C,D,E,F,G,A,B,C)

3. You play a song that uses at least six different musical notes.

4. The musical notes are fairly close to correct pitch.

5. During the presentation, you explain how you designed and constructed your instrument.

6. You explain how to change the instrument's pitch.

7. You explain how to change the instrument's loudness.

8. You explained any problems that were encountered while making the instrument and how you solved them.

9. Your poster/slide show includes diagrams and/or pictures of your musical instrument as you built it.

10. Did you play more than eight musical notes? 11. Did you play a more difficult song in addition

to the required song? 12. Did you make more than one musical

instrument?

Evaluate

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Musical Instrument Rubric

THUMBS UP! DESIGN

and

CONSTRUCTION

ACCURACY

of pitch

PLAYED SONG

OF AT LEAST SIX

DIFFERENT PITCHES

COMMUNICATION

and Accuracy of information

4

Instrument was designed and constructed so it could be played easily.

All of the eight required notes were in perfect pitch. Student may have made an instrument capable of more than 8 notes.

Song was played with a minimum of mistakes. A more difficult song may have been played.

Explanations were clear and accurate about how pitch and loudness can be changed, problems with construction, and the source of idea. Oral report was interesting and included diagrams, pictures.

3

Instrument was designed and constructed so it could be played with a small amount of difficulty.

Most of the required notes were in perfect pitch.

Song was played with some mistakes.

Explanations were fairly clear and accurate about pitch, loudness, problems and idea source. Oral report was fairly interesting and included some diagrams and pictures.

2

Instrument was designed and constructed so the instrument was difficult to play.

Most of the notes were not in perfect pitch.

Song was played

with more mistakes.

Explanations were unclear about pitch, loudness, problems and idea source. Oral report was poorly done and included no diagrams and pictures.

1

Instrument was so poorly constructed that student could not play it.

All eight notes could not be played and they were not in pitch.

Many mistakes were made as the song was played.

Explanations were inaccurate about pitch, loudness, and problems. No source for the idea is given. Oral report includes little information.

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Below, you will find sample TAKS questions. To make it easier to visualize sound waves, some test creators draw sound waves as transverse (up and down) waves. Sound actually travels as longitudinal waves and compressions travel back and forth in the same direction as the wave travels. Please point out to students that the sound waves are pictured as sine waves or oscilloscope waves to highlight the amplitude and frequency of the sound.

Sample T.A.K.S. Questions WAVES: (Items 1 –5) Use the following sine wave representations of sound waves to answer questions 1-2.

Wave A Wave B Wave C Wave D 1. Which wave would be associated with the loudest sound? (TEKS 5D) A Wave A

B Wave B C Wave C D Wave D

2. Which wave would be associated with the highest pitched sound? (TEKS 5D)

A Wave A B Wave B C Wave C D Wave D

3. A sound wave is different from a light wave, because a sound wave is …

(TEKS 5A) A produced by a vibrating object and a light wave is not. B not capable of traveling through a vacuum but light can. C not capable of diffracting and a light wave is.

D capable of existing with a variety of frequencies and a light wave has a single frequency.

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4. A sound wave is a pressure wave with regions of high (compressions) and low pressure (rarefactions) initiated by a vibrating object. Which of the following statements explains why compressions and rarefactions result? (TEKS 5A)

A Sound waves are denser than air and therefore have more inertia, which causes the bunching up of sound.

B Sound waves have a speed which is dependent only upon the properties of the medium.

C Sound is like all waves; it is able to bend into the regions of space behind obstacles.

D Sound waves vibrate in a back-and-forth, longitudinal manner, as it travels through a solid, liquid, or gaseous medium.

5. One tuning fork is struck and placed next to an identical fork. The two forks do not touch. The second tuning fork begins to vibrate as a result of which of the following? (TEKS 5A) A interference

B the Doppler effect

C resonance

D standing wave

Unit Materials Materials Details Sheet A metal coat hanger A pencil with eraser end A short piece of string A wine glass Aluminum baking pans Box with three rubber bands Corrugated plastic tube Eye droppers Large metal slinky Large rubber bands Medium rubber bands Metric rulers Paper Clips Ring stands Scissors Small pebbles Small rubber bands Straws Styrofoam cups Thick rubber bands Three identical bottles Tooth picks Tuning forks

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Vinegar Washers Water The following materials are needed for the unit project: PVC pipes, copper tubing, steel plates, fishing line, bamboo, and any materials that students can use to make their musical instruments.

Background Information for Teachers

What should the IPC learner know about Sound and Waves?

Apply concepts of sound and light waves to everyday situations.

Students should be familiar with models of sound and light waves. This includes experientially grounded understanding of the concepts of frequency, wavelength, speed, energy, refraction, and reflection. Students should be able to compare and contrast how different forms of wave energy are produced, transferred, and detected. For example, explorations of light and sound contribute to explanations of why we are able to see and hear. Contrasted with how other living things see and hear can be an engaging way in which to explore this concept. Additional effective investigations and analyses of relevant applications would include, but are not limited to, simple optical devices and acoustical systems, waves in/on water, music, and noise.

Watch out for the following common misconceptions:

• Sound comes from people's mouths. • Sound comes from wires sparking in electronic devices. Sound actually travels in wires of telephone • Sound is waves of different noises coming from different objects. • When waves go through some objects and come out as music or conversation • Is vibrations in the air that the ear picks up and the brain interprets as sound. • Sound waves cause sound to come out of an object. • Sound moves between particles (empty space). • Matter moves with waves • In a flute… the flute vibrates (column of air) • Sound travels faster in air because there is open space. Sound would be slower in water because the bubbles would

get in the way. It’s hard to hear in solid and water because the stuff gets in the way. Sound can't travel in liquids or solids.

• Hitting and object harder or softer changes pitch. • Pitch changes as the vibration increases or decreases, rubber band, tuning fork… • The Doppler Effect is caused by the horn changing pitch or engineer in train changing it. • Sound travels in one direction like a flash light beam.

References/Resources/ Helpful websites:

The following sites contain information about one or more of these topics: waves, sound, light and musical instruments:

• http://www.42explore.com/musicmnts.htm • http://midwestworldfest.org/japan/frames/2_b_instrum.html • http://www.sciencenews.org/articles/20040306/bob8.asp (Killer Waves: Scientists are learning to predict tsunami risk) • http://www.soc.soton.ac.uk/JRD/SCHOOL/eq/eq001a_wave01.html (Information about all types of waves and their characteristics from the Southampton

sE



Oceanography Centre) • http://www.sciencetech.technomuses.ca/english/schoolzone/Info_Sound.cfm • http://www.glenbrook.k12.il.us/gbssci/phys/class/light/lighttoc.html (Physics Classroom) • http://www.gmi.edu/~drussell/Demos/waves/wavemotion.html (Kettering University wave animation) • http://www.sciencemadesimple.com/index.html (This site has free information. It is not necessary to subscribe)

This site has teacher lesson plans for sound:

• http://school.discovery.com/lessonplans/programs/soundwaves/ These sites have information about I.P.C. including this unit:

• http://www.colorado.edu/physics/2000/waves_particles/wavpart3.html • http://www.sciencenews.org/ (This site does have advertisements) • http://www.school-for-champions.com/science.htm • http://www.thinkquest.org/library/cat_show.html?cat_id=36 • http://www.physicsclassroom.com/ • http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html • http://www.sciencespot.net/Pages/kdzphysics3.html • http://school.discovery.com/lessonplans/physci.html (teacher lessons)

This site has information about seismic waves and earthquakes:

• http://www.usgs.gov

waves unit catch a wave! - indianapolis public schools ... · pdf filewaves unit catch a wave!...

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