Chapter 24 Resource: Energy and Energy Resources

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Name Date Class
1
Laboratory
Activity
Energy Transformations
A small stone thrown up into the air has kinetic energy because it is moving. As it rises higher,
it slows down and its kinetic energy decreases. At the same time, however, its potential energy is
increasing as its position above Earth’s surface increases. When gravity causes the stone to stop
rising and begin falling, its potential energy decreases as its kinetic energy increases. How can you
demonstrate that potential energy can be converted to kinetic energy and vice versa?
Strategy
You will construct a device that changes
energy from one kind to another.
You will observe and measure the distances
the device moves.
You will interpret data in terms of energy
transformations.
Materials
cardboard oatmeal box, with lid
*salt box or other round cardboard
container with lid
scissors
*ice pick
string, 10 cm
large metal washer
rubber band
toothpicks (2)
masking tape, 1 m
meterstick
*Alternate materials
Procedure
1. Use the scissors to punch a small hole in
the center of the bottom of the box.
2. Remove the lid and punch another hole in
the center of the lid.
3. Use the string to tie the metal washer to
the rubber band. Cut off the excess string.
4. From the inside of the box, push part of
the rubber band through the hole in the
bottom. Put a toothpick through the loop
in the rubber band to hold the rubber
band in place, as shown in Figure 1. Pull
any excess rubber band back into the box.
5. While a partner holds the lid close to the
top of the box, stretch the rubber band and
push the other end through the hole in the
lid. Put a toothpick through the loop to
hold the rubber band in place on the lid.
Your device should look like Figure 2.
6. Put the lid on the box.
7. Place the strip of masking tape on the floor
or a table. Place the box on its side at one
end of the tape.
8. Push the box gently, so it rolls along the
tape strip. Ask your partner to mark how
far the box rolls before it stops and begins
rolling back to you. Measure and record
this distance in the table.
9. Repeat step 8 two more times, pushing the
box with a little more force each time.
Figure 1
Loop of
rubber band
Figure 2
Loop of
rubber band
Toothpick
Box
bottom
Toothpick
Box lid
Oatmeal box
Oatmeal box
Washer tied to
rubber band
Energy and Energy Resources 9
Hands-On Activities