C) D) 2. The diagram below shows a worker using a rope to pull a cart.

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1 1. Which graph best represents the relationship between the acceleration of an object falling freely near the surface of Earth and the time that it falls? 2. The diagram below shows a worker using a rope to pull a cart. The workers pull on the handle of the cart can best be described as a force having magnitude, only direction, only both magnitude and direction neither magnitude nor direction 3. A ball is thrown with an initial speed of 10. meters per second. At what angle above the horizontal should the ball be thrown to reach the greatest height? A runner completed the 100.-meter dash in 10.0 seconds. Her average speed was m/s 10.0 m/s 100. m/s 1,000 m/s 5. A baseball dropped from the roof of a tall building takes 3.1 seconds to hit the ground. How tall is the building? [Neglect friction.] 15 m 30. m 47 m 94 m 6. An object travels in a circular orbit. If the speed of the object is doubled, its centripetal acceleration will be halved doubled quartered quadrupled 7. In the diagram below, a box is at rest on an inclined plane. Which vector best represents the direction of the normal force acting on the box? A B C D 8. As the distance between two objects increases, the gravitational force of attraction between them will decrease increase remain the same 9. If the mass of one of two objects is increased, the force of attraction between them will decrease increase remain the same

2 10. Base your answer to the following question on the information and diagram below. A child kicks a ball with an initial velocity of 8.5 meters per second at an angle of 35 with the horizontal, as shown. The ball has an initial vertical velocity of 4.9 meters per second and a total time of flight of 1.0 second. [Neglect air resistance.] 15.A force vector was resolved into two perpendicular components, F1 and F2, as shown in the diagram below. Which vector best represents the original force? The maximum height reached by the ball is approximately 1.2 m 2.5 m 4.9 m 8.5 m 11. A race car starting from rest accelerates uniformly at a rate of 4.90 meters per second 2. What is the car s speed after it has traveled 200. meters? 1960 m/s 62.6 m/s 44.3 m/s 31.3 m/s 12. Which situation describes an object that has no unbalanced force acting on it? an apple in free fall a satellite orbiting Earth a hockey puck moving at constant velocity across ice a laboratory cart moving down a frictionless 30. incline 13. A man is pushing a baby stroller. Compared to the magnitude of the force exerted on the stroller by the man, the magnitude of the force exerted on the man by the stroller is zero smaller, but greater than zero larger the same 14. Which term identifies a scalar quantity? displacement momentum velocity time 16. A man weighs 900 Newtons standing on a scale in a stationary elevator. If some time later the reading on the scale is 1200 Newtons, the elevator must be moving with constant acceleration downward constant speed downward constant acceleration upward constant speed upward 17. What is the acceleration due to gravity at a location where a 15.0-kilogram mass weighs 45.0 newtons? 675 m/s m/s m/s m/s 2

3 18. A car having an initial speed of 16 meters per second is uniformly brought to rest in 4.0 seconds. How far does the car travel during this 4.0-second interval? 32 m 82 m 96 m 4.0 m 19. A 100.-newton force acts on point P, as shown in the diagram below. 24. Which graph represents the motion of an object traveling with a positive velocity and a negative acceleration? The magnitude of the vertical component of this force is approximately 30. N 50. N 71 N 87 N 20. The magnitude of the gravitational force between two objects is 20. Newtons. If the mass of each object were doubled, the magnitude of the gravitational force between the objects would be 5.0 N 10. N 20. N 80 N 21. The diagram below shows a 4.0-kilogram object accelerating at 10. meters per second 2 on a rough horizontal surface. What is the magnitude of the frictional force Ff acting on the object? 5.0 N 10. N 20. N 40. N 22. A 0.50-kilogram puck sliding on a horizontal shuffleboard court is slowed to rest by a frictional force of 1.2 newtons. What is the coefficient of kinetic friction between the puck and the surface of the shuffleboard court? As more force is applied to a steel box sliding on a steel surface, the coefficent of kinetic friction will decrease increase remain the same 25. A baseball player runs 27.4 meters from the batter's box to first base, overruns first base by 3.0 meters, and then returns to first base. Compared to the total distance traveled by the player, the magnitude of the player's total displacement from the batter's box is 3.0 m shorter 6.0 m shorter 3.0 m longer 6.0 m longer 26. A student on an amusement park ride moves in a circular path with a radius of 3.5 meters once every 8.9 seconds. The student moves at an average speed of 0.39 m/s 1.2 m/s 2.5 m/s 4.3 m/s 27. A 750-newton person stands in an elevator that is accelerating downward. The upward force of the elevator floor on the person must be equal to 0 N less than 750 N equal to 750 N greater than 750 N

4 28. Which pair of graphs represents the same motion of an object? 29. If a block is in equilibrium, the magnitude of the block's acceleration is zero decreasing increasing constant, but not zero 30. A car rounds a horizontal curve of constant radius at a constant speed. Which diagram best represents the directions of both the car s velocity, v, and acceleration, a? 31. Base your answer to the following question on the diagram below which represents a 2.0-kilogram mass moving in a circular path on the end of a string 0.50 meter long. The mass moves in a horizontal plane at a constant speed of 4.0 meters per second. The centripetal force acting on the mass is directed toward point A B C D

5 32. Base your answer to the following question on the diagram below which represents a flat racetrack as viewed from above, with the radii of its two curves indicated. A car with a mass of 1,000 kilograms moves counterclockwise around the track at a constant speed of 20 meters per second. Compared to the centripetal acceleration of the car while moving from B to A, the centripetal acceleration of the car while moving from D to C is the same twice as great one-half as great 4 times greater 33. Base your answer to the following question on the diagram below which shows a 2.0-kilogram model airplane attached to a wire. The airplane is flying clockwise in a horizontal circle of radius 20. meters at 30. meters per second. 35. A blinking light of constant period is situated on a lab cart. Which diagram best represents a photograph of the light as the cart moves with constant velocity? 36. A 0.50-kilogram object moves in a horizontal circular path with a radius of 0.25 meter at a constant speed of 4.0 meters per second. What is the magnitude of the object s acceleration? 8.0 m/s 2 16 m/s 2 32 m/s 2 64 m/s 2 If the wire breaks when the airplane is at the position shown, the airplane will move toward point A B C D 34. When the sum of all the forces acting on a block on an inclined plane is zero, the block must be at rest must be accelerating may be slowing down may be moving at constant speed 37. A 1750-kilogram car travels at a constant speed of 15.0 meters per second around a horizontal, circular track with a radius of 45.0 meters. The magnitude of the centripetal force acting on the car is 5.00 N 583 N 8750 N N 38. According to your reference table, Approximate Coefficents of Friction, what is the minimum horizontal force needed to start a 300. N steel block on a steel table in motion? 0.57 N 074 N 171 N 222 N

6 39. Which two graphs best represent the motion of an object falling freely from rest near Earth's surface? 43. The diagram below shows a student throwing a baseball horizontally at 25 meters per second from a cliff 45 meters above the level ground. 40. Two forces are applied to a 2.0-kilogram block on a frictionless horizontal surface, as shown in the diagram below. The acceleration of the block is 5.0 m/s 2 to the right 5.0 m/s 2 to the left 3.0 m/s 2 to the right 3.0 m/s 2 to the left 41. The diagram below represents a block sliding down an incline. Which vector best represents the frictional force acting on the block? A B C D 42. If the net force acting on an object is doubled, the acceleration of the object is halved doubled unchanged quadrupled Approximately how far from the base of the cliff does the ball hit the ground? [Neglect air resistance.] 45 m 75 m 140 m 230 m 44. The greatest increase in the inertia of an object would be produced by increasing the mass of the object from 1.0 kg to 2.0 kg net force applied to the object from 1.0 N to 2.0 N time that a net force is applied to the object from 1.0 s to 2.0 s speed of the object from 1.0 m/s to 2.0 m/s 45. A golf ball is given an initial speed of 20. meters per second and returns to level ground. Which launch angle above level ground results in the ball traveling the greatest horizontal distance? [Neglect friction.] If a 30-Newton force is required to accelerate a 2-kilogram object at 10 meters per second 2, over a level floor, then the magnitude of the frictional force acting on the object is 0 N 10 N 20 N 30 N 47. A rubber block weighing 60. newtons is resting on a horizontal surface of dry asphalt. What is magnitude of the minimum force needed to start the rubber block moving across the dry asphalt? 32 N 40 N 51 N 60 N

7 48. A space probe is launched into space from Earth's surface. Which graph represents the relationship between the magnitude of the gravitational force exerted on Earth by the space probe and the distance between the space probe and the center of Earth? 49. Base your answer to the following question on the diagram below which represents a 5.0-kilogram object revolving around a circular track in a horizontal plane at a constant speed. The radius of the track is 20. meters and the centripetal force on the object is Newtons. 52. The diagram below represents a setup for demonstrating motion. The object's speed is 20. m/s 40. m/s 60. m/s 80. m/s 50. A box is pushed toward the right across a classroom floor. The force of friction on the box is directed toward the left right ceiling floor 51. If two 10.-newton concurrent forces have a resultant of zero, than the angle between the forces must be When the lever is released, the support rod withdraws from ball B, allowing it to fall. At the same instant, the rod contacts ball A, propelling it horizontally to the left. Which statement describes the motion that is observed after the lever is released and the balls fall? [Neglect friction.] Ball A travels at constant velocity. Ball A hits the tabletop at the same time as ball B. Ball B hits the tabletop before ball A. Ball B travels with an increasing acceleration. 53. What is the magnitude of the gravitational force between an electron and a proton separated by a distance of meter? N N N N

8 54. Base your answer to the following question on the graph below which represents the displacement of an object as a function of time. During which time interval is the object accelerating? 0-2 s 2-3 s 3-4 s 4-6 s 55. Two forces, F1 and F2, are applied to a block on a frictionless, horizontal surface as shown below. If the magnitude of the block's acceleration is 2.0 meters per second 2, what is the mass of the block? 1 kg 5 kg 6 kg 7 kg 56. Compared to the force needed to start sliding a crate across a rough level floor, the force needed to keep it sliding once it is moving is less greater the same 57. A 150.-newton force, F1, and a 200.-newton force, F2, are applied simultaneously to the same point on a large crate resting on a frictionless, horizontal surface. Which diagram shows the forces positioned to give the crate the greatest acceleration? 58. As a cart travels around a horizontal circular track, the cart must undergo a change in velocity inertia speed weight 59. A 15-kilogram cart is at rest on a horizontal surface. A 5-kilogram box is placed in the cart. Compared to the mass and inertia of the cart, the cart-box system has more mass and more inertia more mass and the same inertia the same mass and more inertia less mass and more inertia 60. The diagram below represents a car resting on a hill. Which vector best represents the weight of the car? A B C D 61. Base your answer to the following question on the information below. A ball is projected vertically upward from the surface of the Earth with an initial speed of +49 meters per second. The ball reaches its maximum height in 5.0 seconds. (Disregard air resistance.) What is the total displacement of the ball from the time it is thrown until it returns to the point from which it was thrown? 248 m 9.8 m 49 m 0 m

9 62. Which vector diagram best represents a cart slowing down as it travels to the right on a horizontal surface? 65. Which graph represents the relationship between the speed of a freely falling object and the time of fall of the object near Earth's surface? 63. If the mass of one of two particles is doubled and the distance between them is doubled, the force of attraction between the two particles will decrease increase remain the same 64. A net force of 25 Newtons is applied horizontally to a 10.-kilogram block resting on a table. What is the magnitude of the acceleration of the block? 0.0 m/s m/s m/s m/s A rock falls freely from rest near the surface of a planet where the acceleration due to gravity is 4.0 meters per second 2. What is the speed of this rock after it falls 32 meters? 8.0 m/s 16 m/s 25 m/s 32 m/s 67. A stone is dropped from a bridge 45 meters above the surface of a river. Approximately how many seconds does the stone take to reach the water's surface? 1.0 s 10. s 3.0 s 22 s 68. Two 20.-newton forces act concurrently on an object. What angle between these forces will produce a resultant force with the greatest magnitude? 0º 45º 90.º 180.º

10 69. A cart travels with a constant nonzero acceleration along a straight line. Which graph best represents the relationship between the distance the cart travels and time of travel? 70. As shown in the diagram below, a student standing on the roof of a 50.0-meter-high building kicks a stone at a horizontal speed of 4.00 meters per second. 72. A 100.-kilogram cart accelerates at 0.50 meter per second squared west as a horse exerts a force of 60. newtons west on the cart. What is the magnitude of the force that the cart exerts on the horse? 10. N 50. N 60. N 110 N 73. Four forces act concurrently on a block on a horizontal surface as shown in the diagram below. How much time is required for the stone to reach the level ground below? [Neglect friction.] 3.19 s 5.10 s 10.2 s 12.5 s 71. The components of a 15-meters-per-second velocity at an angle of 60. above the horizontal are 7.5 m/s vertical and 13 m/s horizontal 13 m/s vertical and 7.5 m/s horizontal 6.0 m/s vertical and 9.0 m/s horizontal 9.0 m/s vertical and 6.0 m/s horizontal As a result of these forces, the block moves at constant speed to the right moves at constant speed to the left accelerate to the right accelerate to the left 74. Which object has the greatest inertia? a falling leaf a softball in flight a seated high school student a rising helium-filled toy balloon.

11 75. Two forces act concurrently on an object on a horizontal, frictionless surface, as shown in the diagram below. What additional force, when applied to the object, will establish equilibrium? 16 N toward the right 16 N toward the left 4 N toward the right 4 N toward the left