# Physical Science

## Chapter 4: Energy

### Standardized Test Practice

 1. The effect of friction is to convert kinetic energy to _______. A) mechanical energy B) thermal energy C) elastic potential energy D) potential energy 2. According to the graph, the kinetic energy of the rock after 3 seconds is about ________. (4.0K) A) 0 J B) 375 J C) 400 J D) 425 J 3. If no additional force acts on the rock, what is its mechanical energy at 5 seconds? (4.0K) A) 0 J B) -750 J C) 375 J D) 750 J 4. What is the mechanical energy after the rock has fallen for 2 s? (4.0K) A) 0 J B) 750 J C) 200 J D) 550 J 5. What is the potential energy of a 10.0 kg weight suspended 3.0 m above the ground? A) 3.3 J B) 30 J C) 290 J D) 2900 J 6. Which of the the following expressions is the equivalent of 1 Joule? A) kg•m2•s2 B) kg•m/s C) kg•m2/s2 D) kg•m/s2 7. At what point in its motion is the gravitational potential energy of the ball at a maximum? (5.0K) A) at the top of the arc B) just before the bat strikes it C) just after the bat strikes it D) just before it hits the ground 8. Ignoring friction, at what point in its motion is the kinetic energy of the ball at a maximum? (5.0K) A) just before the bat strikes it B) just before it hits the ground C) just after the bat strikes it D) at the top of the arc 9. According to the law of conservation of energy _______. A) energy cannot be created or destroyed B) everthing eventually stops moving C) potential energy must be converted into kinetic energy D) kinetic energy plus potential energy equals mechanical energy 10. What is the kinetic energy of a 1000 kg car traveling at 20 m/s _______. A) 200,000 J B) 20,000 J C) 400,000 J D) 20,000,000 J