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ELECTRICITY

& MAGNETISM

2009-2010

Science is Electrifying

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I. Static Electricity

Lab 1 Stations (7)

Lab 2 Static Electricity Lab 3 Flying Tinsel Reading P. 1-10 with question sheet Bill Nye Video – Static Electricity

II. Lightning

Lightning Fun Quiz Reading P. 10-11 with question sheet

Nova Video on Lightning Current Science “Zapped” article with worksheet

III. Van de Graaf Generator (Optional) Demos/Activities

IV. Batteries

Read p.12-13 with question sheet Lab 4 Wet Cell Batteries

V. Electric Circuits Bill Nye: “Electrical Currents”

Lab 5 - Part 1: Simple Circuits Part 2: Series Circuits Part 3: Parallel Circuits Part 4: Short Circuits Part 5: Challenging Circuits

VII. Electromagnetism

Lab 6 Magic Magnets Read P. 48 on Electromagnets Lab 7 Electromagnets Demonstrate Hand Generator

Chapter 2, sections 2 & 3 in textbook are optional Bill Nye: “Magnetism”

VIII. Electronic Technology (Optional)

Browse Chapter 3, sections 1-3. Create timeline or interview someone about how technology has

changed in their lifetime.

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Name: ___________________

Electricity

Write eleven complete sentences about electricity using the following letters. Each sentence should start with the letter listed.

E L E C T R I C I T Y

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Lab 1: Static Stations

Around the room are some different stations dealing with static electricity. Static electricity is

the buildup of electric charges. The word “static” means stay. As you are creating a charge with the

objects at each station, think about the three methods of creating a charge. You may want to refer to

pages 6 and 7 of your textbook as you complete this lab. Enjoy your shocking events!

Materials:

� Data Chart � Pencil � Balloons

Procedure: 1. Read the directions at each station and fill in your Data Chart as you go.

2. In the second column, write down what you did to the materials to bring about a charge, and also

tell how the objects reacted to each other once the charge was brought on.

3. In the third column, write down the method of charging used to bring about a charge on the

materials. Keep in mind that at some stations, more than one method may be used.

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Lab 1 Data Table

Stations What did you do?

What did you observe?

Method(s) of

Charging:

Friction Conduction Induction

1

2

3

4

5

6

7

8

9

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Name: ______________________

Label the three parts of an atom. (name of part in the blank; type of charge in the box)

Label the balloon diagrams below with the appropriate charge.

A B C D E F

A. _________ C. _________ E. ________ B. _________ D. _________ F. ________

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Triboelectric Series

Human Hands Most Positive

Asbestos Rabbit Fur Glass

Mica Human Hair Nylon Wool Fur Lead Silk Aluminum Paper Cotton Steel Wood Amber Sealing Wax Hard Rubber Nickel, Copper Brass, Silver Gold, Platinum Sulfur Acetate, Rayon Polyester Styrene (Styrofoam) Orlon Saran Polyurethane Polyethylene Polypropylene Vinyl (PVC) Silicon Teflon Most Negative

The above list is from Nature’s Electricity, p.63 by Charles K. Adams. © 1987 Tab Books, #2769

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Name: ________________________

Lab 2: Static Electricity

Background Information “Static electricity” can be very exciting to work with but do you really know what it is? Many

people define it as the buildup of electrical charges while many other people object to using the term “static electricity.” These last people believe that the term makes no sense! Can you explain why they believe this?

Static electricity is probably the most exciting when it’s “discharged.” As you’ve already experienced, this is when the sparks and zaps fly! But what exactly does it mean when static electricity is discharged? See if you can figure out a good explanation.

Materials � Piece of Styrofoam pad � Fur or wool cloth � Electrophorus

Procedure and Questions 1. What kind of charge does the Styrofoam have? 2. What kind of charge does the fur or wool cloth have? 3. What kind of charge does the electrophorus have? 4. Place the Styrofoam pad on a flat surface and rub vigorously with fur or wool. 5. What kind of charge does the Styrofoam now have? 6. What kind of charge does the fur or wool now have? 7. While holding it by the upside-down cup, carefully place the electrophorus on top of the Styrofoam

sheet. 8. Slowly bring your knuckle to the aluminum edge of the electrophorus. 9. What happened when your knuckle got to within about 0.5 cm of the edge? 10. Why did this happen? 11. What kind of charge did the electrophorus have before you touched it? 12. Why did it have this kind of charge? 13. What kind of charge did the electrophorus have after you touched it? 14. Why did it have this kind of charge?

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Lab 3.0 Flying Tinsel

Materials: 1 acrylic rod (lucite or plexiglass) 12’’ to 18’’ long and ¾’’ to 1’’ around. You may also use 1 large balloon, round or long, 1 acrylic plate 15’’ square or larger or one square of styrofoam. 1 wool cloth (can use silk or flannel also)

1 tinsel loop approximately 2’’ long

Background: When a neutral acrylic rod is vigorously rubbed with a wool cloth, negatively

charged electrons from the cloth pass to the rod, creating a charge imbalance in the rod and the cloth. Because the rod now has more negatively charged particles than positively charged particles, it is no longer neutral; instead, it is now negatively charged. On the other hand, the wool cloth has lost electrons, causing it to become positively charged.

Now you can get the rod and a piece of Christmas tinsel to perform some interesting “tricks.” The charged rod will draw a piece of tinsel toward it. Once the tinsel gets close enough to the rod, some of the rods excess (extra) electrons will flow to the tinsel, thus causing the tinsel to become negatively charged. As we know, according to the “law of electrical charges,” like charges repel and opposite charges attract. So what do you think will now happen to the tinsel?

Procedure: 1. Take the piece of tinsel and tie it in a loop. 2. Rub the acrylic rod vigorously with the wool cloth. 3. Hold the charged rod in one hand. With the other hand, throw the tinsel loop into

the air away from your body. Next, move the rod under the tinsel. The loop will move toward the rod and then away.

4. The tinsel may fall to the floor, but continue trying until the tinsel is suspended in the air.

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Name: ________________________ Questions for pages 4-10. Atoms and Charge

1. All matter is composed of very small particles called _______________. __________ are made up of even smaller particles called ___________, _____________, and _____________.

2. Protons and electrons are ____________ particles and neutrons are not. Charges Can Exert Forces

3. A charged object exerts a force – a _______ or a ________ - on other charged objects. 4. The law of electric charges states that _______ _________ ______ and ____________

___________ __________. 5. ____________ are positively charged and ___________ are negatively charged. Because they

are oppositely charged, protons and electrons are ___________ to each other. 6. Without the attraction between protons and electrons, ___________ would fly away from the

nucleus of an atom. The Electric Force and the Electric Field

7. The force between charged objects is an ___________ _________. 8. The strength of the electric force depends on

a. b.

9. An __________ ___________ is a region around a charged particle that can exert a force on

another charged particle. Charge It!

10. Why don’t atoms have a charge?

11. If the atoms of an object lose _____________, the object becomes _____________ charged. 12. If the atoms gain ______________, the object becomes ____________ charged. 13. The 3 ways to charge an object are:

a. b. c.

Friction

14. ______________ two objects together can cause electrons to be “wiped” from one object and transferred to another.

Conduction 15. ______________ occurs when ________________ are transferred from one object to another

by _________ contact.

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Induction

16. Charging by ___________ occurs when charges in an uncharged object are ____________ without direct contact with a charged object.

Conservation of Charge

17. When you charge objects by any method, ____ ___________ are created or __________. _____________ simply move from one atom to another, producing objects or regions with ______________ __________.

18. Because charges are _______ __________ or _____________, charge is said to be _______________.

Detecting Charge

19. What can an electroscope be used for?

20. Sketch what an electroscope looks like. Moving Charges Conductors

21. A ______________ is a material in which charges can move ___________. 22. List four good conductors.

a. b. c. d.

23. Why should you avoid using electrical devices near water? Insulators

24. An ___________ is a material in which charges can ______ easily move. 25. List five good insulators.

a. b. c. d. e.

Static Electricity

26. ___________ ___________ is the buildup of __________ __________ on an object. 27. When something is __________ it is not ____________.

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Name: ____________________

Period: _____

“Static Electricity” (Bill Nye video)

1. Electricity is a flow of ____________________.

2. Sometimes electrons don’t flow. They build up to cause ____________________ ____________________.

3. The word “static” is from the word that means ____________________.

4. Van de Graff generator:

a. Electric charges are deposited on the ____________________ belt, then the charges are redeposited on the ____________________ ___________________.

b. Once the ball is touched, electrical ____________________ are deposited.

c. A person’s hair stands up because all charges on the individual strands of hair are the ____________________; therefore they ________________.

d. ____________________ will occur when charges jump from one object to another.

5. One example of things that easily or readily attract an electric charge is ____________________.

6. When electrons “jump off,” it is called “____________________.”

7. When electrons discharge, they go to “____________________” many times through the ground wire.

8. Some electrical cords have a third prong. It is for ____________________.

9. Static charges build up on things when ___________________ together.

10. Electroscopes detect ____________________ ____________________.

11. When electrical charges build up so much that they fall to ground, ____________________ occurs.

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Lightning Fun Quiz

1. True/False A car’s rubber tires will insulate and therefore protect a

person in the car from a lightning strike. 2. True/False Enclosed buildings offer complete protection from

lightning strikes. 3. True/False If a person is hit by lightning, he or she will have burns

to prove it.

4. True/False Lightning never strikes the same place or person twice.

5. True/False Buildings of any type are safe places to be in an electrical

storm. 6. True/False Lightning always strikes the tallest objects. 7. True/False You must be in the midst of a thunderstorm to be hit by lightning.

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Questions for Pages 10-11 Name: _________________________________ Lightning Electric Discharge

1. The loss of static electricity as ______________ move off an object is called ____________ _____________.

2. Electric discharge can occur _____________ or _____________. Lightning

3. One of the most dramatic examples of electric discharge is ____________.

4. Who was the first person to discover that lightning was a form of electricity?

5. ____________________ forms in the following way: water or ice droplets in clouds rub together producing _____________ which causes _____________ electric charges to build up on the bottom of the cloud. These _____________ charges induce a ________________ charge on the ground. When the charges build up enough the cloud’s _____________ charges jump to the ground, creating ________________.

6. What did Benjamin Franklin invent?

7. A ______________ __________ is a pointed rod connected to the ground by a wire.

8. Objects, such as lightning rods, that are in contact with the Earth are

________________. 9. What does “grounded” mean?

10. Why is it dangerous to be at the beach or on a golf course during a lightning storm?

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Name: _____________________ Per.: _____

“Zapped!” (Current Science, Jan. 16, 2004, vol. 89 iss. 11)

Read the article on p. 10-11 and answer the following questions. 1. About _____________ people are killed by lightning each year in the United States.

2. How many people are struck by lightning each year in the United States? __________

3. How hot is lightning? _________________________

4. If lightning is so hot, why doesn’t it seriously damage human tissue?

_____________________________________________________________________

5. Why does lightning typically kill people?

_____________________________________________________________________

6. List at least four harmful effects of lightning strikes:

a. __________________________

b. ___________________________

c. ___________________________

d. ___________________________

7. Most lightning strikes are associated with what kinds of clouds?

_____________________________________________________________________

8. List two examples of when lightning might not be associated with a thunderstorm:

a. _______________________________________________________________

b. _______________________________________________________________

9. Scientists aren’t positive what causes lightning but they believe it’s similar to what?

_____________________________________________________________________

10. Lightning hits the ground when ____________________ charged particles in a

____________________ and _____________________ charged particles on the

____________________ build up.

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Van de Graaf Generator

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Questions for Pages 12-13 Name: ___________________________ Batteries Batteries Are Included

1. Energy is defined as the __________ _____ _____ _________. 2. Energy cannot be __________ or ____________; it can only be ____________

into other types of _____________. 3. A _________ is a device that produces an ____________ __________ by

converting ___________ energy into _____________ energy. 4. A _____________ also converts ______________ energy into

_______________ energy and is made of several __________.

Parts of a Cell

5. A mixture of chemicals that conducts a current is an ______________. 6. An ____________ is the part of a cell through which _____________ enter or

exit. Types of Cells

7. What are the two types of cells? a. b.

8. __________ ________ contain liquid electrolytes. An example would be _____________________.

9. __________ ________ contain electrolytes that are solid or pastelike. An example would be __________________.

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Lab 4: Wet Cell Batteries

Did you know that many fresh foods such as potatoes and lemons are capable of producing an

electric current? Ordinary saltwater will do the same thing. Actually, almost anything produces

electricity. This investigation will allow you to see how these ordinary materials along with two

metals can produce electricity.

Materials:

• Citrus Fruit • Potato • Copper Strip • Zinc Strip • Galvanomet

er

• Liquid Solutions

• Beakers • Test Leads

Procedure:

1. Work in groups as directed by your teacher.

2. At each station, the metals are inserted into the substance being tested. Take the

other end of the test lead and attach it to the galvanometer.

3. Check for a reading on the galvanometer and record your data on the table.

Vocabulary Terms: 1. Amperes (amps) –

2. Galvanometer -

3. Microamps –

4. Electrolyte –

5. Electrode –

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Lab 4 Data Chart

Stations Electrolyte Electrodes Galvanometer Reading (µµµµA)

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

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Name __________________________

Lab 4 Questions:

1. What is electricity? (electric current see p.12) 2. There are 2 types of cells (see p 13). What kind of cell did we test in this lab?

3. Why did we use two different metals as the electrodes? (p.12)

4. Why is it important to have an electrolyte in a cell? (p.12)

5. What was the galvanometer used for in this lab?

6. What unit of measure did we use when determining the current of our cells?

7. Of the foods and liquids, which one produced the most electricity?

8. Why do you think one was better than the other cells?

9. Were there certain times when your galvanometer did not give you a reading at all?

10. What do you think caused this?

11. What causes the galvanometer to change directions on the scale?

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Name: _________________________

“Electrical Current” (Bill Nye video)

1. Electricity is the __________________ of tiny particles called

__________________.

2. “__________________” is an old word for “go around.”

3. The flow of __________________is a lot like the flow of water.

4. What would you have to do in order to get shocked at a bumper car ride

at an amusement park?

___________________________________________________________

___________________________________________________________

______________________.

5. Your brain uses the same amount of power as a __________________

light bulb.

6. When current electricity was first discovered, some people thought that

___________________________________________________________

______________.

7. In some materials, like metals, __________________ can jump from

atom to atom easily.

8. Things that let electricity go through them easily are called

__________________.

9. Things that don’t let electricity go through them easily are called

__________________.

10. If something kind of lets electricity go through it, it’s called a

__________________.

11. __________________ is similar to pressure. The higher it is, the more

easily electrons can “jump.”

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12. The number of electrons flowing through a wire is referred to as

__________________.

13. Why would you probably be electrocuted (or severely shocked) if you

put both hands in the water next to a South American eel?

____________________________________________

___________________________________________________________

_______________.

14. “AC” stands for __________________ __________________. We call

it this because

___________________________________________________________

_______________.

15. “DC” stands for __________________ __________________. We call

it this because

___________________________________________________________

_______________.

16. Birds can safely sit on one wire because their bodies don’t

__________________ a __________________.

17.Why do plugs have two prongs? _______________________________________________ _________________________________________________________________________.

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Lab 5: Electric Circuits

Part 1: Simple Circuits

� Read pages 22-23

1. What is a circuit ? (page 22)

2. What 3 things does a circuit consist of? (page 22)

3. What would be considered the energy source in the simple circuit that you just constructed?

4. What is the definition of a load? (page 22)

5. What would be considered the load in the simple circuit that you just constructed?

6. What does it mean when you have a closed circuit? (page 23)

� Set up a simple circuit like the one shown on page 23. � Use your battery tray, one bulb, one switch, and connect them with alligator

clips.

7. When you close the switch, what happens?

8. When you open the switch, what happens?

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Part 2: Series Circuits � Read page 24 about Series Circuits.

9. Define series circuit.

10. What do loads in a circuit do to the current?

11. Where would you want to use a series circuit?

� Using your battery tray, set up a series circuit like the one shown on page 24. � This time use 3 bulbs instead of one. � You do not need a switch for this circuit.

12. Are all three bulbs the same brightness?

13. Are the three bulbs as bright as the bulb in the simple circuit that you made earlier?

14. What happens if you carefully unscrew one light bulb?

15. Does it make any difference which bulb you unscrew?

16. What happens to the brightness of the bulbs if you add another bulb to the circuit (4 bulbs instead of 3)?

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Part 3: Parallel Circuits � Read page 25.

17. Define parallel circuit .

18. Do the loads in a parallel circuit have the same current in them?

19. Is the voltage for each load the same or different?

20. Why would you want parallel circuits in your house?

� Now make a parallel circuit like the one shown on page 25. � Use your battery tray and 3 bulbs. � You do not need a switch.

21. What happens if you carefully unscrew one light bulb?

22. Are all four bulbs the same brightness?

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Part 4: Short Circuits � Read pages 26-27.

23. What is a short circuit?

24. What can cause short circuits?

25. What might happen if you have too many loads (overload) on a circuit?

26. What are 2 safety devices used in homes to prevent currents in circuits from getting too high?

Teacher Demonstration of Short Circuits!

27. Explain what happened to the wire. (This is an example of a short

circuit.)

28. What would happen when two bare wires touch in your house?

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Part 5: Challenging Circuits #1 Directions: Using only 5 test leads, wire the doorbell buzzer so that either switch will independently operate the doorbell. Label the center power source terminal positive and other terminal negative. Sketch the test leads on the diagram.

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#2 Directions: Using only 9 test leads, wire the lights in the three rooms so that each one operates independently. Label the center power source terminal positive and other terminal negative. Sketch the test leads on the diagram.

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#3 Directions: Using only 5 test leads wire the stairway light so that each switch operates the light independently. Label the center power source terminal positive and other terminal negative. Sketch the test leads on the diagram.

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Lab 6: Magic Magnets Magicians sometimes use magnets to help them do their tricks. Just how a

magnet works may be a surprise to you. In this activity you’ll be doing some

investigations to find out more about magnets.

Materials:

� 2 flat Magnets

� Paper

� Iron Filings in a Jar

� String

� Paperclips

� Clay

� Wire

� Iron Nail

� Battery

� Cylinder Magnet

Procedure:

Part 1: Magnetism is a force that can move things. Explore materials that are attracted

to your magnet and materials that are not attracted to your magnet. List these

materials in the following data table under the appropriate column heading.

Table 1 Sticks to Magnet Doesn’t Stick to Magnet

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Read pages 38 –39.

1. How are most of the things that stick to a magnet alike?

__________________________________________________________________

2. How are most of the things that do not stick to a magnet alike?

__________________________________________________________________

3. Where were magnets first discovered and by who?

________________________________ _________________________________

4. What did these people call the mineral?

_________________________________________________________________

5. What are 3 properties of a magnet?

_______________________ ______________________ ____________________

Part 2: Using two magnets, try to put the ends together.

6. What happens?

__________________________________________________________________

7. Now turn one of your magnets around and try putting the ends together. What

happened this time?

__________________________________________________________________

8. Each end of the magnet has a name. One end is called the ________________

____________ and the other is called the ___________ ___________. (Page 39)

9. Magnet Force means that unlike poles ______________ each other and like

poles _____________ each other. (Page 39)

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Part 3: Place the cylinder shaped magnet on the table and cover it with paper. Lightly

sprinkle the filings on the paper. Tap the side of the paper gently, and notice the

pattern that the filings make. It should look similar to the pictures on page 40.

Sketch what you see in the space below:

Read page 40 -41

10. The above sketch shows the magnet’s _________________ ________________.

11. The closer the lines are, the stronger the force. Magnets are strongest at the

_________________________________________________________.

12. Three metals that have magnetic properties are __________________________,

_________________________, and ___________________________.

13. If you could look inside a magnet, you’d see that it looks as though it was made of

many little magnets which are called domains. A magnet will lose some of its

strength if these domains are out of alignment. List 2 ways that this might

happen. __________________________________________________________

_________________________________________________________________.

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Part 4: Try to make a paperclip magnet by rubbing the paperclip on the magnet several times in the same direction.

14. Can you pick up other paperclips with this magnet (or can you at least see some

attraction between the two)? __________________________________________________________________

15. What three types of metals can you magnetize?

__________________, __________________, and _______________. (Page 41)

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Lab 7: Electromagnets

You have learned about electricity in chapter 1, and you’ve just finished learning about magnetism

in the previous lab. Is it possible that these two forces have a connection? Yes! You will discover what

that connection is in this next lab.

Materials: � Battery � Iron nail � Paperclips � Wire

Procedure: � Use an energy source, an iron nail, some paperclips, and wire. � Starting in the middle of the nail and with the center of the wire, wrap the wire around the nail. Be

careful not to overlap the wire. � Put this device near some paperclips.

1. What happened?

__________________________________________________________________ � Now connect the wire and nail to the battery and bring it near some paperclips.

2. This time, what happened?

__________________________________________________________________ This type of “battery powered” magnet is called an electromagnet. You will learn more about this later.

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Name: ________________________

“Magnetism” (Bill Nye Video)

1. Magnetism is ____________________.

2. Magnetism comes from ____________________ in the Earth and the Earth is so full

of these things that the Earth is like a giant ____________________.

3. The most common mineral that can be made into a magnet is ____________________.

4. Only three things will stick to a magnet: ____________________,

____________________, and ____________________. Nothing else will stick!

5. Magnetism comes from ____________________ electrons.

6. Likes ____________________; opposites ____________________.

7. If you break a magnet in half, you get two smaller magnets. They each have a

“____________________ pole” and a “____________________ pole.”

8. There’s no way to get a magnet with just ____________________

__________________.

9. Poles that are alike ________________________________________ each other; poles

that are not alike ________________________________________ each other.

10. ____________________ attract; ____________________ repel.

11. Whenever ____________________ is flowing, a magnetic field forms.

12. When something is magnetized, its domains _____________________________ and

this causes the object to become a magnet.

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13. What causes Earth to be a giant magnet?

______________________________________________________________________

______________________________________________________________________

______________________________________________________________________

14. The Earth’s magnetic field helps cause the

______________________________________________________________________

15. Why aren’t Venus, Mars, and the Moon magnetic?

______________________________________________________________________

______________________________________________________________________

______________________________________________________________________

16. Magnetic or Not?????????

a. Screwdriver ______

b. Dollar bill ______

c. Levitating train ______

d. Iron butterfly ______

e. Cassette tape ______

f. Photograph ______

g. Aluminum bike ______

h. Penny ______

i. Jupiter ______

j. Plastic ______

k. Your shoe ______

l. Your desktop ______

m. Horseshoe ______