41. If two objects collide and stick together, what will happen to their velocities? a. velocities will increase c. velocities will stay the same b. velocities will decrease d. none of the above ____ 42. If two objects collide and stick together, what will happen to their overall momentum? a. momentum will increase c. momentum will stay the same b. momentum will decrease d. none of the above ____ 43. When the speed of an object is doubled, its momentum a. remains unchanged c. quadruples b. doubles d. halves ____ 44. If the momentum of an object changes and its mass remains constant, a. it is accelerating c. there is a force acting on it b. its velocity is changing d. all of the above ____ 45. The purpose of crumple zones on a car is to a. decrease time of impact. c. increase force of impact. b. increase the time of impact. d. decrease the impulse during impact. ____ 46. The reason padded dashboards are used in cars is that during a collision they a. increase the time of impact. c. increase the force of impact. b. decrease the impulse. d. decrease the momentum. ____ 47. The total momentum before the collision is ____________ the total momentum after the collision. a. less than b. the same as c. more than ____ 48. An egg is thrown at a wall and then at a bed sheet. The force of impact will be a. Greater against the wall b. Force is equal c. Greater against the sheet ____ 49. Cart A is pulled with 2 N for 2 seconds, and Cart B is pulled with a 1 N for 3 seconds. Which cart experiences the greater impulse? a. Cart B b. Cart A c. they are the same ____ 50. A 2.0 kg basketball has a momentum of 4.0 kgm/s. What is the ball's speed? a. 0.5 m/s b. 2.0 m/s c. 4.0 m/s d. 8.0 m/s ____ 51. A bowling ball is moving at 6.0 m/s and has a momentum of 24.0 kgm/s. What is the ball's mass? a. 0.3 kg b. 4.0 kg c. 24.0 kg d. 144.0 kg ____ 52. A soccer ball experiences an impulse of 4.0 Ns over 2.0 s . How much force was exerted on the ball? a. 0.5 N b. 2.0 N c. 4.0 N d. 8.0 N ____ 53. A baseball experiences an impulse of 48.0 Ns when a force of 8.0 N acts on it. How long was the force applied to the ball? a. 0.2 s b. 6.0 s c. 48.0 s d. 384.0 s ____ 54. Which of the following is a true statement? a. Energy can be created or destroyed. c. Energy is the rate of doing power. b. Energy can be stored or transferred. d. The unit for energy is the Watt. ____ 55. Why does the total amount of energy stay constant in a system? a. energy is not created or destroyed c. energy is lost b. energy is gained d. energy is not converted ____ 56. A red car and blue car are raised to the same elevation on service-station lifts. If the red car is twice as massive as the blue, how does the potential energy of the red car compare to the blue car? a. PE of the blue car c. 2x PE of the blue car b. PE of the blue car d. 4x PE of the blue car ____ 57. Objects have kinetic energy because of their mass and... a. distance b. velocity c. acceleration d. force ____ 58. Kinetic energy is the energy of an object that is due to the object's _____. a. inertia b. momentum c. motion d. position ____ 59. Objects can have potential energy because of a spring constant or a. height b. velocity c. acceleration d. force ____ 60. Potential energy is the energy of an object that is due to the object's _____. a. inertia b. momentum c. motion d. position ____ 61. Where on the U ramp did the skateboarder have the most potential energy? a. At the top b. Partially down c. At the bottom. ____ 62. Where on the U ramp did the skateboarder have the most kinetic energy? a. At the top b. Partially down c. At the bottom. ____ 63. When the distance an object moves is zero, the work done on the object is also zero. a. Always true b. Depends on situation c. Always false ____ 64. How much work is being done when a student holds a 3 kg grapefruit at 2.7 m above the ground? a. 0 J b. 2.7 J c. 8.1 J d. 79.4 J ____ 65. How much work is being done with 243 N of force over 436 meters? a. 105948 J b. 0.56 J c. 1.79 J d. 679 J ____ 66. How much force is used to move an object 325 meters with 193 J of work? a. 62725 N b. 0.59 N c. 1.68 N d. 518 N ____ 67. How far did an object move if 366 J of work uses 229 N? a. 83814 m b. 0.63 m c. 1.6 m d. 595 m ____ 68. What is the kinetic energy of a 7 kg toy car that has a speed of 5 m/s? a. 87.5 J b. 17.5 J c. 175 J d. 122.5 J ____ 69. What is the mass of a toy car that has a speed of 4 m/s and 57 J of energy? a. 28.5 kg b. 7.1 kg c. 14.3 kg d. 0.07 kg ____ 70. What is the potential energy of a trampoline that has spring constant of 5 N/m and is stretched 1.2 m? a. 6.5 J b. 5.4 J c. 13 J d. 48.6 J ____ 71. What is the spring constant of a trampoline that is stretched 1.8 m and 62 J of energy? a. 68.9 kg b. 34.4 kg c. 34.4 kg d. 0.03 kg ____ 72. What is the potential energy of a 8 kg book at 4 m off the ground? a. 32 J b. 39.2 J c. 313.6 J d. 627.2 J ____ 73. What is the mass of a book at 4 m off the ground and 71 J of energy? a. 174 kg b. 1.8 kg c. 17.8 kg d. 0.06 kg ____ 75. Who stated that "every object in the universe attracts every other object"? a. Newton b. Kepler c. Hooke ____ 76. What is the direction of the force that acts on clothes in the spin cycle of a washing machine? a. Inward b. Down c. Outward d. Tangential ____ 77. The velocity is always _____ to the line of a circle. a. outwards b. towards center c. tangent d. faster ____ 78. If the mass of Earth increased, with no change in radius, your weight would _____. a. stay the same b. decrease c. increase ____ 79. If the radius of Earth decreased, with no change in mass, your weight would _____. a. not change b. increase c. decrease ____ 80. Speedy, the sloth,weighs 90 pounds on Earth. How much will Speedy weigh on the moon? a. 0 lbs b. 15 lbs c. 90 lbs d. 180 lbs ____ 81. Inky, the octopus, weighs 360 pounds on Earth. How much will Inky weigh on Jupiter? a. 0 lbs b. 60 lbs c. 360 lbs d. 920 lbs ____ 84. Which planet would have the longest year? a. Mercury b. Mars c. Jupiter d. Neptune ____ 85. The fastest moving planet in a solar system is _____. a. Mercury b. Mars c. Jupiter d. Neptune ____ 86. A child spins a yo-yo. In 30 seconds, it spins 6 times. What is its period? a. 2 s b. 5 s c. 10 s d. 30 s ____ 87. An amusement park ride completes a revolution in 10 s. If it has a radius of 10 m, what is its velocity? a. 2 m/s b. m/s c. 20 m/s d. 10 m/s ____ 89. In order to form an electric circuit, you need to have a. wires or conductors to connect everything. b. a power source. c. a light bulb or some resistance. d. a complete path for the current. e. all of the above ____ 90. In order for current to flow in a circuit, you must have a. a switch that is open. b. a complete path for the current. c. two light bulbs in parallel. d. two light bulbs in series. e. all of the above