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1. How much is done by if a 20 kg block 7. A student pulls a block 3.0 meters along a horizontal at 10 m/s is slowed down to 4m/s? surface at constant . The diagram below shows the components of the exerted on the A) 84 B) 100 joules block by the student. C) 125 joules D) 200 joules E) 840 joules 2. How much work is done by a 2,000 kg moving at a constant 0.5 c far from any source of gravitational or electromagnetic force in 5 meters? A) 0 joules B) 250 c joules C) 250 c 2 joules D) 5,000 c joules E) 50,000 c joules 3. How much work is done lifting a 40 newton block 2 How much work is done against friction? meters? A) 6 J B) 18 J C) 24 J D) 30 J E) 42 J A) 20 joules B) 38 joules 8. A horizontal force of 40 N is used to push a block C) 40 joules D) 42 joules along a horizontal surface at a constant of 2 E) 80 joules meters per second. How much work is done on the 4. How much work is done pushing a 10 kg box up a block in 6 seconds? frictionless 30 degree incline 5 meters high at a A) 80 J B) 120 J C) 180 J D) 240 J E) 480 J constant rate? 9. How much work is done as a box of weight W is A) 500 joules B) 700 joules vertically lifted with an g, to a height h? C) 1,000 joules D) 1,500 joules E) 2,000 joules A) Wh B) Whg2 5. A 30 newton box is being pushed at a constant rate. C) Wh The coefficient of friction is 0.1 what is the work g done pushing the box 10 meters against friction? D) 2Wh A) 3 joules B) 10 joules g C) 15 joules D) 30 joules E) 2Wh E) 60 joules 10. If L, M and T denote the dimensions of length, , 6. In order to demonstrate some concepts of , a and , respectively, what are the dimensions of physics teacher pushes against a wall with a force of ? 300 N for 5 s. As you can imagine, the wall remains A) M/T2 B) ML/T2 stationary. How much work does the teacher do on C) ML2/T2 D) M/L2 the wall in this time period? E) T2/M A) 0 J B) 0.017 J 11. A person lifts a box with a mass of 2.0 kg from the C) 60 J D) 750 J ground to a shelf 0.5 m high. The work that E) 1500 J does on the box is equal to A) –10 J B) –5 J C) 0 J D) 5 J E) 10 J 12. An object with a mass of 2 kg is attached to the end of a 3 m long string and is whirled horizontally in a circle with a constant speed of 5 m/s. When the object has traveled half a revolution, how much work has been done by the ? A) 0 J B) 50 J C) 100 J D) 150 J 16. A block of mass M is pulled by a constant force F at E) 300 J an angle of 30° relative to the ground for a distance of L meters. What is the net work done? 13. A vertical force of 500 N acts on a 12 kg mass over a horizontal of 2 m. The work done by A) MLFcos30 the force is B) LFcos30 C) Lcos30 A) 0 J B) 24 J D) Fcos30 C) 1000 J D) 6000 J ML E) 12000 J E) MLcos30 F 17. Which of the following is not a vector quantity? A) B) Velocity C) Work D) E) Force 18. If a 5,000 kg runaway truck is traveling 30 m/s, how 14. A woman pushes a lawn mower with a force of F at high must a ramp be to bring the truck to a complete an angle to the ground. If F = 20N and = 30°, stop? what is the net work done in moving the lawnmower A) 25 meters B) 45 meters 5m? C) 90 meters D) 1,80 meters A) 25 J B) 50 J E) 250 meters C) 86.67 J D) 14.4 J 19. A 1 kg radio controlled car is traveling at 10 m/s. E) 35 J When the car is 5 meters from a cliff the 15. A ball of mass 16 kg on the end of a string is spun at hits the . How much force is required to stop a constant speed of 2.0 m/s in a horizontal circle the car? with a radius of 1 m. What is the work done by the A) 5 newtons B) 10 newtons centripetal force during one complete revolution? C) 20 newtons D) 50 newtons A) 0 J B) 16 J C) 32 J D) 8 J E) 4 J E) 100 newtons 20. Just before hitting a nail, a 2 kg is moving at 10 m/s just before it hits a nail. If the wood exerts a constant 180 newton force on the nail, how far does the nail go? A) 0.1 meters B) 0.6 meters C) 1 meter D) 2 meters E) 4 meters 21. A 10 newton block sliding on a frictionless surface 26. A person does 100 joules of work in pulling back the goes up a ramp 3 meters high. If the block is initially string of a bow. What will be the initial speed of a traveling at 10 m/s what is the final velocity of the 0.5- arrow when it is fired from the bow? block? A) 20 m/s B) 50 m/s A) 5 m/s B) 7 m/s C) 200 m/s D) 400 m/s C) 10 m/s D) 30 m/s E) 800 m/s E) 40 m/s 27. Which of the following graphs best represents the 22. If a 200 kg cart going 30 m/s brakes with a force of kinetic energy K of a particle as a function of the 1,000 newtons how far will it travel before coming momentum p of the particle? to a stop? A) B) A) 9 meters B) 18 meters C) 90 meters D) 180 meters E) 900 meters 23. Which of the following is true of a 1 kg mass and a 5 C) D) kg mass that both fall from rest from the same height? A) the force felt due to gravity is the same on both B) their initial potential are equal 28. A 100 W motor propels an object with a mass of 4 C) they lose at the same rate kg for 2 s from rest. Its final velocity will be D) they have the same kinetic energy upon hitting A) 5 m/s B) 10 m/s the ground C) 20 m/s D) 40 m/s E) their are equal E) 100 m/s 24. What happens to the energy of a as it 29. An object with a mass of 2 kg increases in speed hits the ground with a certain downward velocity? from 4 m/s to 12 m/s in 3 s. The total work A) energy is converted into performed on the object during this time is kinetic energy. A) 16 J B) 64 J C) 128 J D) 256 J E) 512 J B) Elastic Potential Energy is converted into 30. A rail gun is able to accelerate a with a gravitational potential energy mass of 4 kg from rest to 100 m/s in 5 s. Calculate C) Kinetic energy is converted into energy. the work done on the projectile by the force of the D) Kinetic energy is converted into elastic rail gun. potential energy and heat. 2 E) Kinetic energy is converted into gravitational A) 1.0 × 10 J energy. B) 5.0 × 102 J C) 2.0 × 104 J 25. If an object sliding on a rough surface experiences 5 an increase in kinetic energy of E while it is pushed D) 1.0 × 10 J by a constant force F through a distance d, what is E) Cannot be determined from the information the force to due to friction? provided. A) F d – E B) (Fd – E)/d C) (F – E)/d D) Fd E) E/d – F Base your answers to questions 35 through 37 on the picture below, which represents a plane 10 m in length with a coefficient of kinetic friction of 0.2, inclined at an angle of 53º. A block of weight 30 N is placed at the top of the plane and allowed to slide 31. Two balls of equal size are dropped from the same down. height from the roof of a building. One ball has mass M and the other has a mass 2M. When the balls reach the ground, how do the kinetic energies of the two balls compare? (Neglect friction) A) M has one-fourth the kinetic energy of 2M. B) M has one-half the kinetic energy of 2M. C) M has the same amount of kinetic energy as 2M. D) M has twice the amount of kinetic energy as 2M. E) M has four the amount of kinetic energy as 2M. 32. How much energy is required to stop a car of mass 35. The work done on the block by friction during its 10 100 kg traveling at 25 m/s? m slide down the plane is most nearly A) 1,150 J B) 21,150 J A) 10 J B) 12.0 J C) 31,250 J D) 32,250 J C) 18 J D) 24 J E) 42,250 J E) 36 J 33. A car with kinetic energy 20,000 J travels along a 36. The work done on the block by the gravitational horizontal road. How much work is required to stop force during its 10 meter slide down the plane is the car in 5 s? most nearly A) 0 J B) 20,000 J A) 60 J B) 180 J C) 260 J D) 300 J E) 390 J C) 4,000 J D) 8,000 J 37. The velocity of the block after its 10 m slide down E) 16,000 J the plane is most nearly 34. An object at rest weighs 100 N on earth. It gains A) 8.2 m/s B) 8.6 m/s 100 J of kinetic energy. What is its velocity? C) 8.9 m/s D) 9.7 m/s A) m/s B) m/s E) 10.0 m/s C) m/s D) m/s E) m/s 38. A block of mass m moving with initial velocity v0 moves over a rough surface with coefficient of kinetic friction ƒ. How long does it take for the block to come to a complete stop? A) B)

C) D)

E) 39. A particle is fired straight up out of a cannon. 41. If the object has a mass of 1.4 kg, what is its velocity Which of the following graphs best represents its at 5.0 m? kinetic energy K as a function of time t? A) 0.2 m/s B) 2.0 m/s A) B) C) 5.0 m/s D) 9.25 m/s E) 15 m/s

42. An object that starts at rest from the origin is pushed by a constant force of 10 N has a position given by x (t) = 5t2. What is the delivered to the object C) D) by the force at time t = 1 s? A) 50 J B) 50 W C) 100 J D) 100 W E) 125 W E) 43. If the power delivered to an object by a force acting on it is given by P(t) = t 3 – 2t and the velocity of the object is given by v(t) = 2t, what is the force acting on the object in terms of t? A) F(t) = t 3 – 4t 3 Base your answers to questions 40 and 41 on B) F(t) = t the force vs. distance graph below, which is for an C) F(t) = t 2/2 – 1 object being pushed along a straight line, starting at D) F(t) = 3t 2 – 2 rest. E) More information is needed to determine the force 44. If a force moves an object of mass m so that its velocity is given by v(t) = 4t – 2, what is the power exerted by that force? A) 0.5m(4t – 2)2 B) 4m(4t – 2) C) 4m(2t 2 – 2t) D) 4m E) m(4t – 2) 45. What is the expression of the kinetic energy of an object of mass 5 kg whose acceleration is given by a (t) = 4t – 5 and that is initially at rest? A) 5(4t – 5) B) 5(2t 2 – 5t) C) 5(2t 2 – 5t)2 D) 2.5(2t2 – 5t)2 E) 2.5(4t – 5)2 40. After the object has moved a distance of 2.0 m, how much work has been done on it? A) 5 J B) 10 J C) 15 J D) 20 J E) 25 J 46. An object with an initial potential energy k 52. The potential energy of an object is given by experiences a given by F(x) = x 2 U(x) = 0.5kx2 + 3kx, where U is in joules, x is in + 2 over the interval 0 × 2. What is the meters and k is a constant. What is the force acting equation for the potential energy U of this object? on the object when x = 0? A) U(x) = x 3/3 + 2x + k A) –3k B) –k C) Zero D) k E) 3k 3 B) U(x) = –x /3 – 2x – k 53. A 50 kg car travels along a straight track along the x C) U(x) = –x 3/3 – 2x + k -axis according to the equation x(t) = t2 + 4t + 5, D) U(x) = –x 3/3 – 2x where x is in meters and t is in seconds. What is the E) U(x) = x 3/3 + 2x car’s kinetic energy after 1 s? 47. An object is pushed by a force given by F(x) = 6x – A) 900 J B) 1000 J 4. What is the amount of work done to push the C) 1500 J D) 2000 J object 4 m. E) 2705 J A) 16 J B) 20 J C) 32 J D) 44 J E) 80 J 54. A force given by F(x) = 6x + 3x2 acts upon a 48. The velocity of an object of mass m is given by the projectile that starts from rest at the origin. How equation v = 2x + 4. What is an expression for the much work is done on the 5 kg projectile if it travels kinetic energy of the object? 5 m? A) 2m A) 155 J B) 175 J C) 200 J D) 225 J E) 400 J B) m(2 + x) 55. The position of a of mass 1000 kg moving C) m(4x + x2) on a straight track along the x-axis is given by the D) m(2x2 + 8x + 8) equation x(t) = t3 – t2 – 6t, where x is in meters and t E) m(8x2 + 4x3 + x4/2) is in seconds. What is the instantaneous force acting on the vehicle at t = 3 s? 49. A force acting on an object of mass 3 kg is given by the equation F(x) = 6x + 2, where F is in Newtons A) Zero B) 3000 N and x is in meters. If the object starts at rest, what is C) 6000 N D) 12000 N the final velocity of the object as it travels from x = E) 16000 N 0 to x = 4 m? 56. Which of the following statements concerning a A) 2 m/s B) 4 m/s skier in a valley is true if friction and air resistance C) 6 m/s D) 8 m/s are negligible? E) 12 m/s I. The skiers speed is maximum at the bottom of the valley 50. A 10 kg particle's acceleration is given by the II. The skiers speed is at a minimum at the top of 2 equation a(t) = 4t, where a is in m/s and t is in the valley seconds. The particle is initially at rest at the origin. III. The skiers potential energy is zero at the top of What is the particle's kinetic energy at t = 5 s? the valley A) 2.5 kJ B) 5 kJ A) I only B) II only C) 12.5 kJ D) 125 kJ C) I and II only D) II and III only E) 250 kJ E) I, II and III 51. A force acting on an object given by the function 57. What is the velocity of a particle after falling 10 2 F(x) = 3x + 4, where F is in Newtons and x is in meters if its initial velocity is 10 m/s? meters. What is the change in the object’s kinetic energy as it moves from x = 1 to x = 3 m? A) 10 B) 10 C) 20 m/s D) 150 m/s A) 26 J B) 27 J C) 31 J D) 34 J E) 36 J E) 300 m/s 58. What is the minimum velocity a toy car has to travel 63. A 1 N weight depresses a 20 cm. What is the in order to survive going through a loop of radius 0.2 spring constant? meters if? A) 0.0025 N/cm B) 0.005 N/cm A) m/s B) 2 m/s C) 0.05 N/cm D) 20 N/cm C) 4 m/s D) 8 m/s E) 400 N/cm E) 16 m/s 64. If a spring with force constant 0.01 N/cm has a 59. 5 kg bowling ball in a assembly is given potential energy of 2.0 how far was the spring an initial velocity of 10 m/s. What is the maximum depressed? height reached by the ball? A) 0.04 cm B) 0.2 cm A) 1 meter B) 2.5 metes C) 20 cm D) 200 cm C) 5 meters D) 25 meters E) 400 cm E) 50 meters 65. How much work is done compressing a spring 10 cm 60. A pendulum of mass m on a massless string of with constant 0.01 N/cm? length l is displaced an angle . What is the A) 0.0001 Joules B) 0.001 Joules maximum velocity of the pendulum? C) 0.1 Joules D) 0.5 Joules A) B) E) 1 Joule C) D) 66. A spring with a force constant of 0.01 N/cm is E) depressed 10 cm what is the force exerted on the 61. In general, if the of a system is raised spring? to a higher gravitational potential and the system is A) 0.001 N B) 0.01 N otherwise unchanged, C) 0.1 N D) 10 N A) the system becomes more stable E) 1,000 N B) the system becomes less stable 67. A spring with a force constant of 0.05 N/cm sits C) the total energy of the system decreases vertically. How far is it depressed when a 5 N D) the kinetic energy in the system decreases weight is placed on it? E) the system does work on its environment A) 25 cm B) 50 cm C) 100 cm D) 500 cm E) 1,000 cm 68. A 3 kg object is dropped from a height of 4 m onto a spring. The maximum compression of the spring is 0.5 m. What is the spring constant? A) 120 N/m B) 240 N/m C) 480 N/m D) 600 N/m E) 960 N/m 69. A spring of constant 50 N/m is used to launch a mass 62. A block of mass 1 kg at rest slides down a across a rough surface. The spring is compressed frictionless inclined plane as shown in the picture. 0.05 m and released. How much work is done by The plane is sloped at an angle of 30° relative to the friction in order to bring the mass to rest? ground. When the block slides to the ground, its change in kinetic energy is most nearly A) 0.063 J B) 0.125 J C) 1.25 J D) 2.5 J A) +10J. B) –10J. C) +15J. D) –15J. E) +20J. E) 100 J 70. Which of the following is true of the energy of a 74. A 1.0 kg object is suspended from a spring with spring-mass system? constant k = 16 N/m. The mass is pulled 0.25 m downward from its equilibrium position and allowed A) The total energy is greatest when the velocity is to oscillate. What is the maximum kinetic energy of greatest. the object? B) The total energy is greatest when the displacement is greatest. A) 0.25 J B) 0.50 J C) The potential energy is greatest when the C) 1.0 J D) 2.0 J displacement is least. E) 4.0 J D) The kinetic energy is greatest when the 75. Five identical masses of mass M are suspended by a potential energy is least. spring stretched a distance of L. If three of the E) The total energy varies based on the position of masses are removed, what is the potential energy the mass. stored in the spring? 71. A block of mass 5.0 kg is hung from a vertical A) B) spring stretching it 0.40 m. The amount of energy C) D) stored in the spring is most nearly E) 5 MgL A) 0.40 J B) 0.80 J 76. A billiard ball of mass m strikes a soft ball of mass C) 8.0 J D) 10 J 2m with kinetic energy E. If energy is conserved E) 20 J what is the velocity of the heavier ball if all its 72. Which graph below best represents the relationship energy is transferred? between the potential energy stored in a spring (PE) A) B) and the force required to keep the spring in equilibrium (F)? C) D) A) B) E)

77. A block of mass m is sliding on a frictionless surface with velocity v. If the block is acted on by a force F C) D) for a distance x what is its new velocity? A) B) C) D)

73. Which graph below best represents the relationship E) between the potential energy stored in a spring (PE) 78. A block of mass m is attached to a placed on a and the change in the length of the spring from its vertical spring with force constant k. If the spring is equilibrium position (X)? depressed a distance x, what is maximum height A) B) reached by the block? A) B) C) D) E)

C) D) 79. A student drops a 0.02 N coin from a 4 meter high 83. If an object is released at the beginning of the track, window onto a spring with a constant of 0.01 N/cm. which of the following is true at point E? How far is the spring depressed? Neglect air A) It is in static equilibrium resistance. B) It is losing kinetic energy A) 0.0008 cm B) 0.08 cm C) It is in dynamic equilibrium C) 2 cm D) 4 cm D) There is a net force acting on the object E) 8 cm E) Its kinetic energy is 25 J 80. A bullet of mass m is shot into a spring with 84. At which point is an object at rest in stable constant k. If the spring depresses a distance x equilibrium? what was the incident velocity of the bullet? A) A B) B C) C D) D E) E A) B) C) D) E) 85. At which point would an object at rest be in unstable equilibrium? Base your answers to questions 81 through 85 on the diagram below which shows a frictionless track. A) A B) B C) C D) D E) E

86. include which of the following?

I. Joule II. Ampere-volt per second III. Volt-coulomb A) I only. B) I and II only. C) I and III only. D) II and III only. E) I, II, and III. 87. A student throws a stone upward at an angle of 30°. Which statement best describes the stone at the 81. If an object of mass 5 kg is released from rest at the highest point that it reaches? beginning of the track, what is its velocity at point D? A) Its acceleration is zero. B) Its acceleration is at a maximum. A) 1 m/s B) 1.4 m/s C) Its potential energy is at a minimum. C) 2 m/s D) 2.2 m/s D) Its kinetic energy is at a minimum. E) 3 m/s E) Its potential and kinetic energies are equal 82. Which of the following best describes the of 88. Units of energy include which of the following? an object as it approaches point B, if it was released from rest at the beginning of the track? I. Newton-meter A) It is losing potential energy only. II. Ampere-volt B) It is gaining kinetic energy only. III. Volt-coulomb C) It is gaining potential energy and gaining A) I only. B) I and II only. kinetic energy C) I and III only. D) II and III only. D) It is losing potential energy and gaining kinetic E) I, II, and III. energy E) It is gaining heat energy, gaining kinetic energy, and losing potential energy 89. Base your answer to the following question on the 93. A crate with mass m slides down a frictionless ramp following situation. with length L and vertical height h. The crate's change in kinetic energy from the top to the bottom An object weighing 10 N swings at the end of a rope is equal to: that is 0.72 m long as a simple pendulum. At the 2 A) mL 2 bottom of the of the swing, the tension in the string 2 is 12 N. B) –mL 2 C) –mgh What is the maximum height above its lowest point D) mgh that the object reaches? E) Cannot be determined from the information A) 0.036 m B) 0.060 m given. C) 0.072 m D) 0.144 m Base your answers to questions 94 and 95 on the E) 0.360 m diagram below. In the diagram, a box of mass m is 90. An object is falling from a height of h in a vacuum sliding down a frictionless ramp of length L with an and reaches a final velocity of v. When the object incline of q to the horizontal. The mass takes t has fallen a distance of h/2, its velocity is seconds to slide down the ramp. A) v

B) v 2 C) v 4 94. The work done by gravity on the object is equal to D) v A) mgL E) 4v t 91. An object with a mass of 4 kg is released from rest at B) mgLcosq the top of a ramp with length 10 m that makes an t angle of 30º with the horizontal. The coefficient of C) mgLcosq kinetic friction between the block and the ramp is D) mgLsinq 0.4. The speed the block will have when it has E) Cannot be determined from the information traveled 5 m down the ramp is most nearly given. A) 3.9 m/s B) 5.6 m/s 95. If released from rest at the top, the velocity of the C) 7 m/s D) 7.9 m/s block at the bottom of the ramp will be E) 10.4 m/s A) B) 92. A block with a mass of 10 kg slides down a frictionless inclined plane of length 25 m and height C) D) 20 m. It's speed at the bottom is most nearly A) 15 m/s B) 20 m/s E) C) 30 m/s D) 37 m/s E) 45 m/s 96. Base your answer to the following question on the 100. A 5 kg object slides 100 m down a frictionless following information. inclined plane dropping 45 m. It then slides along a horizontal surface with a coefficient of kinetic Two balls of different masses are set at a height of 3 friction of 0.75 until it stops. How long does it take m above the ground on a frictionless table. The ball to stop after it leaves the inclined plane? on the left is of mass 2M and the ball on the right has A) 3.0 s B) 4.0 s a mass of 3M. They both are released simultaneously and slide onto the part of the table 2m above the C) 6.0 s D) 12.0 s ground. E) 15.0 s 101. Base your answer to the following question on the picture below which shows a 3 kg block sliding 50 m down a frictionless inclined plane dropping a What is the total energy of the system? distance of 30 m. A) +1Mg B) +5Mg C) +10Mg D) +15Mg E) +20Mg 97. A man standing a certain height above the ground throws a rock of mass 1 kg straight up with an initial What is the kinetic energy of the block at the end of velocity of 10 m/s. A few moments later, the rock the drop? hits the ground with a kinetic energy of 450 J. If the man dropped this rock from rest, how much kinetic A) 90 J B) 300 J energy would it have right before it hits the ground? C) 500 J D) 900 J A) 100 J B) 200 J C) 300 J D) 400 J E) 500 J E) 1500 J 98. A man standing a certain height above the ground 102. A block is slid up an incline with an initial velocity throws a rock straight up with an initial velocity of v, such that the frictional force is less than the 10 m/s. A few moments later, the rock hits the gravitational force on the incline. Which is true ground with a kinetic energy of 450 J. If the man about the final speed of the block? threw this rock horizontally with an initial velocity A) Final speed is greater than the initial speed of 10 m/s at the same height, how much kinetic B) Final speed is less than the initial speed energy would it have just before it hits the ground? C) Final speed is zero A) 50 J B) 100 J C) 450 J D) 800 J E) 950 J D) Final speed is equal to the square root of twice 99. Base your answer to the following question on the the height times g information below. E) The final speed is equal to the initial speed 103. A 1 kg block is placed on an incline of 53 degrees A 4.0 kg block rests at the edge of a platform that is with a spring at the bottom. The incline has a 20 m above level ground. The block is launched height of 4 meters and the spring has a force horizontally with an initial velocity of 15 m/s. constant of 5 N/cm. If the spring is depressed 4 The object's kinetic energy when it hits the ground is cm, what is the coefficient of kinetic friction? most nearly A) 0.25 B) 0.4 C) 0.66 D) 0.75 E) 1 A) 450 J B) 800 J C) 1050 J D) 1250 J E) 2450 J 104. A spring with a force constant of 1.5 N/cm is Base your answers to questions 109 through 111 on depressed 20 cm. How high is a 1 kg mass the following information. launched if 0.1 Joules are lost to air resistance on the way up? A roller coaster car starts at Point A and travels along a frictionless slope traveling to Point E which is at a A) 0.5 cm B) 1 cm slightly lower height. C) 2 cm D) 3 cm E) 4 cm 105. A spring accelerates a 1 kg mass on ice. The mass comes to a table top and after 1 meter it comes to a stop. If the spring constant is 10 N/m and the spring is depressed 5 cm, what is the coefficient of kinetic friction? A) 0.00125 B) 0.0125 C) 125 D) 250 E) 1250 109. The car's speed is the fastest at which point? 106. A baseball with mass 2 kg is thrown vertically A) A B) B C) C D) D E) E upward with a velocity of 10 m/s. If it lands with a 110. If it can be assumed that the car has the same speed velocity of 5 m/s, how much energy has been at points A and E, which of the following exhausted by air resistance? statements is true? A) 5 Joules B) 15 Joules A) The net work done in this system is 0 J. C) 75 Joules D) 125 Joules B) The net work done in this system is positive. E) 150 Joules C) The net work done in this system is negative. 107. How much energy is required to push a 50 kg mass D) The net work done in this system is 0 for the 15 m across a surface with a coefficient of friction roller coaster, but positive for the slope. of 0.3 at a constant velocity? E) The net work done in this system is positive A) 43.3 J B) 650 J for the roller coaster, but 0 for the slope. C) 2250 J D) 6350 J 111. If it can be assumed that the car has the same speed E) 9750 J at points A and E, which of the following can be a valid explanation about the roller coaster car? 108. An object is dropped off a cliff of height h and is subjected to an average force of air resistance of F. A) The Gravitational Potential Energy is lower at If the object has a mass of m, the kinetic energy it Point E than at Point A. gains during the fall will be equal to B) The Gravitational Potential Energy is higher at Point E than at Point A. A) mgh B) mgh + F C) Friction exists between the wheels of the roller C) mgh – F D) mgh + Fh coaster car and the track. E) mgh – Fh D) The roller coaster car loses Kinetic Energy between A and C. E) The roller coaster car gains Kinetic Energy between A and C. 112. A 4.0 N force is used to accelerate a 2.0 kilogram 119. A small heater puts out 1,500 watts of heat block from rest to a velocity of 6.0 m/s. If the on average. How long will it take the space heater force was applied over a distance of 15 meters, the to add 3,750 joules of energy to the room? coefficient of kinetic friction between the block and A) 0.4 s B) 2.5 s the surface is most nearly C) 5 s D) 1.25 s A) 0.03 B) 0.04 C) 0.06 D) 0.08 E) 0.12 E) 6.25 113. A horizontal force F is used to push a 3.0 kg block, 120. A skater is sliding on ice at a constant speed of 20 initially at rest, across a floor, with a constant m/s for 20 seconds. What is the average power acceleration of 2.0 m/s2. If the frictional force consumed by the skater? between the block and the floor is 4 Newtons, how much work is done by force F on the block to A) 0 watts B) 1 watt move it 15 meters? C) 20 watts D) 200 watts E) 400 watts A) 60 J B) 90 J C) 120 J D) 150 J E) 210 J 121. What is the average power consumed by a crane 114. A 3 kg object slides 90 meters down a frictionless lifting a 150 kg crate 10 meters to a ledge in 15 inclined plane dropping 45 meters. It then slides seconds along a horizontal surface with a coefficient of kinetic friction of 1.0 until it stops. How far from A) 100 watts B) 1,000 watts the base of the inclined plane does it stop? C) 1,5000 watts D) 22,500 watts A) 400 m B) 450 m E) 225,000 watts C) 500 m D) 525 m 122. How many joules of energy are consumed by a 40 E) 4,500 m watt light bulb in 1 hour of being turned on? 115. Of the following, which is NOT a unit of power? A) 4 joules B) 40 joules C) 240 joules D) 2400 joules A) Watt E) 144,000 joules B) Joule per second C) Kilogram meter squared per second cubed 123. Of the following, which is NOT a unit of power? D) Kilowatt-hour A) Watt 116. Of the following, which is NOT a unit of power? B) Joule per second C) Kilogram meter squared per second cubed A) Watt D) Kilowatt-hour B) Joule per second E) Ampere-volt C) Kilogram meter squared per second cubed D) Kilowatt-hour 124. A crate with mass 40 kg is pulled by a worker along a surface at a constant velocity for 10 m. If 117. Of the following, which is NOT a unit of power? the crate is pulled for 5 s, and the coefficient of A) Watt kinetic friction between the surface and the crate is B) Joule per second 0.5, the power exerted by the worker over this time C) Kilogram meter squared per second cubed is most nearly D) Kilowatt-hour A) 20 W B) 40 W 118. a 60 kg climber reaches the top of a 40 meter cliff C) 100 W D) 200 W in 8 minutes. What is the average power consumed E) 400 W by the climber? A) 0.5 watts B) 5 watts C) 50 watts D) 300 watts E) 1920 watts 125. Base your answer to the following question on In 128. A toy rocket travels upward at 100 m/s. If the the diagram, a box of mass m is sliding down a rocket has to exert a constant force of 40 newtons frictionless ramp of length L with an incline of q to to counter gravity and air resistance, how many the horizontal. The mass takes t seconds to slide watts does the engine put out? down the ramp. A) 2.5 watts B) 40 watts C) 100 watts D) 4,000 watts E) 40,000 watts 129. A runner is moving at 4 m/s. She experiences air resistance force of 20 newtons. What power is she consuming The power exerted by gravity during the slide is A) 5 watts B) 10 watts A) mgsinq t C) 20 watts D) 40 watts E) 80 watts B) mgtcosq C) mgtsinq 130. A boat motor exerts a force of 7,000 newtons of D) mgLsinq force to maintain a speed of 7 m/s how much t power does the engine have? E) mgLcosq A) 1,000 watts B) 3,500 watts t C) 7,000 watts D) 21,000 watts E) 49,000 watts 131. As a helicopter takes off its engine exerts a force of 250,000 N if the aircraft ascends at 40 m/s how much power does the engine have? A) 0 watts B) 625 watts C) 6250 watts D) 250,000 watts 126. A block of mass M is moved up a frictionless E) 10,000,000 watts incline by a constant force F. The incline has an 132. A 1 kg block slides down a 30 degree incline at a angle . The block moves up the incline at a constant 4 m/s. How much power is dissipated in constant velocity of 5 m/s. What is the power the form of heat by friction? required accomplish this situation? A) 0 watts B) 8 watts A) B) C) 20 watts D) 40 watts C) D) E) 400 watts E) 133. A 500 N student expends an average power of 250 127. What power is needed to lift a person of mass 50 kg W to climb a 6 m vertical rope at constant velocity. a vertical distance of 5.0 m in 20 seconds? How long does it take for the student to climb the A) 12.5 W B) 25 W rope? C) 60 W D) 125 W A) 1 s B) 2 s C) 3 s D) 6 s E) 12 s E) 210 W 134. A 300 N object is lifted 10 m by a crane at a constant rate in 15 s. The average power expended to lift the object is A) 2 W B) 20 W C) 200 W D) 2,000 W E) 20,000 W 135. A helicopter lifts a large crate weighing 4000 N 141. The acceleration of an object is given by the expending a constant power of 8 kW. The crate is equation a(t) = 2, where a is in m/s2 and t is in moving upward at a constant velocity of seconds. The object is initially at rest at the origin. A constant force of 30 N acts on the object. What A) 2 m/s B) 4 m/s is the power delivered to the object at t = 9 s? C) 8 m/s D) 16 m/s E) 50 m/s A) 240 W B) 360 W C) 540 W D) 600 W 136. A crane lifts a box upward that weighs 2000 N at a constant speed of 8 m/s. What is the power input of E) 810 W the crane to lift the box? 142. The velocity of an object is given by the equation v(t) = 2t + 5, where x is in m/s and t is in seconds. A) 250 W B) 1,250 W A constant force of 6 N acts on the object. What is C) 8,000 W D) 16,000 W the power delivered to the object at t = 3 s? E) 32,000 W A) 55 W B) 61 W 137. How much power is needed to lift a 100 kg block C) 66 W D) 71 W vertically upward at a constant speed of 5 m/s? E) 77 W A) 2,500 W 143. The position of an object is given by the equation B) 5,000 W x(t) = t2 + 3t + 4, where x is in meters and t is in C) 7,500 W seconds. A constant force of 10 N acts on the D) 10,000 W object. What is the power delivered to the object at E) 0 W because the object is at a constant t = 5 s? velocity A) 100 W B) 104 W 138. A person pushes an object with a mass of 50 kg C) 130 W D) 134 W across a surface with a coefficient of friction of 0.2. E) 200 W If the box moves with a constant velocity of 2.0 m/s, the power supplied to the box by the person is 144. The power delivered by an object is given by the equation P(t) = 6t – 3, where P is in Watts and t is A) 20 W B) 25 W in seconds. How much work is done by the object C) 50 W D) 100 W during the interval 0 < t < 4 s? E) 200 W A) 16 J B) 21 J C) 24 J D) 36 J E) 48 J 139. If a mass of 10 kg moves with the velocity v(t) = t2 – 2t + 1, what is the power exerted by the 145. The work done by an object is given by the 2 force pushing the mass at t = 2? equation W(t) = 3t – 5t + 1, where W is in Joules and t is in seconds. What is the power delivered by A) 5 W B) 10 W the object at t = 2? C) 20 W D) 30 W A) 3 W B) 6 W C) 7 W D) 8 W E) 10 W E) 50 W 140. The power delivered to an object at t = 2 s is 170 W. The position of the object along the x-axis is given by the equation x(t) = 3t2 + 5t + 1, where x is in meters and t is in seconds. Which of the following is closest to the force acting on the object? A) 8 N B) 9 N C) 10 N D) 11 N E) 12 N Answer Key ap energy review

1. E 37. A 73. B 109. C 2. A 38. E 74. B 110. A 3. E 39. C 75. B 111. C 4. A 40. B 76. C 112. D 5. D 41. D 77. D 113. D 6. A 42. D 78. A 114. E 7. C 43. C 79. D 115. D 8. E 44. B 80. A 116. D 9. A 45. D 81. C 117. D 10. C 46. C 82. D 118. C 11. A 47. C 83. C 119. B 12. A 48. D 84. B 120. A 13. A 49. C 85. D 121. B 14. C 50. C 86. C 122. E 15. A 51. D 87. D 123. D 16. B 52. A 88. C 124. E 17. C 53. A 89. C 125. D 18. B 54. C 90. A 126. C 19. B 55. E 91. A 127. D 20. B 56. C 92. B 128. D 21. A 57. B 93. D 129. E 22. C 58. B 94. D 130. E 23. E 59. C 95. D 131. E 24. D 60. A 96. D 132. C 25. B 61. B 97. D 133. E 26. A 62. E 98. C 134. C 27. A 63. C 99. D 135. A 28. B 64. D 100. B 136. D 29. C 65. D 101. D 137. B 30. C 66. C 102. B 138. E 31. B 67. C 103. C 139. C 32. C 68. E 104. C 140. C 33. B 69. A 105. A 141. C 34. C 70. D 106. C 142. C 35. E 71. D 107. C 143. C 36. C 72. B 108. E 144. D Answer Key ap energy review

145. C