1. As a pendulum swings from position A to position B as shown in the diagram, its total mechanical energy (neglecting friction) A) decreases B) increases C) remains the same 2. Base your answer to the following question on the diagram below. Which represents a 2.0-kilogram mass placed on a frictionless track at point A and released from rest. Assume the gravitational potential energy of the system to be zero at point E. As the mass travels along the track, the maximum height it will reach above point E will be closest to A) 10. m B) 20. m C) 30. m D) 40. m 3. As a pendulum moves from the bottom of its swing to the top of its swing, the A) kinetic energy of the pendulum increases B) kinetic energy of the pendulum remains the same C) potential energy of the pendulum decreases D) potential energy of the pendulum increases
4. A pendulum is made from a 7.50-kilogram mass attached to a rope connected to the ceiling of a gymnasium. The mass is pushed to the side until it is at position A, 1.5 meters higher than its equilibrium position. After it is released from rest at position A, the pendulum moves freely back and forth between positions A and B, as shown in the diagram below. 7. The wrecking crane shown below is moving toward a brick wall which is to be torn down. At what point in the swing of the wrecking ball should the ball make contact with the wall to make a collision with the greatest kinetic energy? A) 1 B) 2 C) 3 D) 4 What is the total amount of kinetic energy that the mass has as it swings freely through its equilibrium position? [Neglect friction.] A) 11 J B) 94 J C) 110 J D) 920 J 5. This question has only three choices. As a ball falls freely toward the ground, its total mechanical energy A) decreases B) increases C) remains the same 6. A 1-kilogram rock is dropped from a cliff 90 meters high. After falling 20 meters, the kinetic energy of the rock is approximately A) 20 J B) 200 J C) 700 J D) 900 J
Base your answers to questions 8 and 9 on the diagram below which represents a block with initial velocity v1 sliding along a frictionless track from point A through point E. 8. The kinetic energy of the block will be greatest when it reaches point A) A B) B C) C D) D 9. The velocity of the block will be least at point A) A B) B C) C D) E 10. A 25-gram paper cup falls from rest off the edge of a tabletop 0.90 meter above the floor. If the cup has 0.20 joule of kinetic energy when it hits the floor, what is the total amount of energy converted into internal (thermal) energy during the cup s fall? A) 0.02 J B) 0.22 J C) 2.2 J D) 220 J 11. A car uses its brakes to stop on a level road. During this process, there must be a conversion of kinetic energy into A) light energy B) nuclear energy C) gravitational potential energy D) internal energy
12. The diagram below represents a 35-newton block hanging from a vertical spring, causing the spring to elongate from its original length. Determine the spring constant of the spring. Base your answers to questions 13 and 14 on the information and diagram below and on your knowledge of physics. A jack-in-the-box is a toy in which a figure in an open box is pushed down, compressing a spring. The lid of the box is then closed. When the box is opened, the figure is pushed up by the spring. The spring in the toy is compressed 0.070 meter by using a downward force of 12.0 newtons. 13. Calculate the total amount of elastic potential energy stored in the spring when it is compressed. [Show all work, including the equation and substitution with units.] 14. Calculate the spring constant of the spring. [Show all work, including the equation and substitution with units.]
Base your answers to questions 15 and 16 on the information below. A student produced various elongations of a spring by applying a series of forces to the spring. The graph below represents the relationship between the applied force and the elongation of the spring. 15. Calculate the energy stored in the spring when the elongation is 0.30 meter. [Show all work, including the equation and substitution with units.] 16. Determine the spring constant of the spring. Base your answers to questions 17 and 18 on the information below. A vertically hung spring has a spring constant of 150. newtons per meter. A 2.00-kilogram mass is suspended from the spring and allowed to come to rest. 17. Calculate the total elastic potential energy stored in the spring due to the suspended 2.00-kilogram mass. [Show all work, including the equation and substitution with units.] 18. Calculate the elongation of the spring produced by the suspended 2.00-kilogram mass. [Show all work, including the equation and substitution with units.]
Answer Key Rev Con/Spring 1. C 2. D 3. D 4. C 5. C 6. B 7. C 8. C 9. D 10. A 11. D 12. 350 N/m 13. Equation and substitution with units or for an answer, with units, that is consistent with the student's response to questions 71. 14. Equation and substitution with units. 15. PEs = 0.90 J 16. 20. N/m 17. 18.