1. 'Energy can neither be created nor destroyed' is a statement of the   Law of Conservation of Energy   Law of Conservation of Electric Charges   Law of Conservation of Matter   Hint Half-n-half Clue   2. The energy acquired by a body because of its motion is called potential energy.   True   False   3. If an engine does 639 J of work in 9 seconds, its average power is   648 W   71 W   630 W   5751 W   Half-n-half Clue   4. Kinetic energy of a body in motion equals the product of half its mass and the square of its _______   velocity   distance   acceleration   Half-n-half Clue   5. A body loses 8379 J of potential energy in falling through 95 m. If the gravitational acceleration is 9.8 m s-2, then the body has a mass of   88 kg   9 kg   855 kg   931 kg   Half-n-half Clue   6. A machine that produces 102 J of work by using 120 J of energy has an efficiency of   17 J   85 %   18 J   15 %   Half-n-half Clue   7. When a current is supplied by a battery, _______ energy is converted to electrical energy.   nuclear   mechanical   chemical   Half-n-half Clue