Revision Questions

1. Name an object which has a lot of a) Gravitational potential energy, b) kinetic energy, c) elastic potential energy, d) heat energy

2. What is energy measured in? What is the symbol for this unit?

3. What do all types of energy have in common?

4. What is an energy transfer?

5. What transfer takes place when a) a wind up toy car moves? b) a candle burns? c) light falls on a solar cell?

6. A motor does 500J of useful work when supplied with 2000J of electrical energy. What is its efficiency?

7. A bicycle is 30% efficient ( 0.3 ). If it is supplied with 1000J of energy how much useful work does it do?

8. Much of the wasted energy by an electric drill is in the form of heat. Where does it go?

9. Why will this wasted energy never do useful work again?

10. One way to reduce energy loss from your house would be to have triple glazing.
       Would this be effective? Would this be cost effective? Explain the difference.

11. Why should we try to reduce the amount of energy we consume in our homes? ( 3 reasons )