1. 1. A roller coaster car never returns to its starting height because energy gets lost along the way.
false

2. Where does friction oppose motion on a roller-coaster car?
Between the wheels of the car and the track
Between the car and the surrounding air
Between the car’s axle and the wheels
Between the car and the passenger

3. 3. The original amount of potential energy of a roller-coaster is converted into kinetic energy and ________________________________ energy as the car races down the hill.
thermal

4. 4. The potential energy of the car at the top of the second hill of a roller coaster is equal to the original potential energy of the car at the top of the first hill.
false

5. 5. A roller coaster is involved in a closed system. List its parts.
tracks
cars
surrounding air

6. The law of conservation of energy states that energy can be neither
____________________________ nor
_____________________________.
created
destroyed

7. Look at figure 24 on page Which forms of energy are converted from electrical energy that enters the light bulb?
Light energy
Thermal energy warming the bulb
Thermal energy caused by friction on the wire
Chemical energy

8. 8. During an energy conversion, energy is rarely converted to thermal energy.
false

9. 9. Why is it impossible to make a perpetual motion machine?
A perpetual motion machine would run forever without any additional energy. BUT because of waste thermal energy that results from energy conversions, the only way to keep a machine moving is to keep putting energy into it.