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**DO NOT DEPEND ENTIRELY ON THIS PRACTICE TEST FOR YOUR PREPARATION** P H Y S I C S I - P R A C T I C E E X A M - 2010 EQUATIONS and CONSTANTS Round off all acceleration due to gravity on Earth to: g = 9.81 m/s2 Linear Motion: v average v d t v average Free Fall: Force: d t v original v final 2 d = 1/2 gt2 (when acceleration is constant) Weight: Fgravity = mg = mv v t v = gt Fnet = ma Momentum: a (when velocity is constant) or w = mg P R A C d = 1/2 at T I C E total momentum (before) = total momentum(after) m1 v1 m2 v 2 m1 v1 m2 v 2 m1 v1 + m2 v2 = m3 v3 (for objects that combine in a collision) Friction: F = N (FF = FN) Impulse: Ft = (mv) Potential Energy: Work: W = Fnet d Power: P = W/t Impulse = F t GPE = mgh Kinetic Energy: KE = 1/2mv2 KE=PE=Work Conversion Factors: 1.0 mile = 1610 m Metric prefixes: kilo-, hecto-, decka-, base unit, deci-, centi-, milli- Percent Error 1.0 kg = 2.2 lbs Experimental Value - Accepted Value Accepted Value Displacement and Vectors: X = Xf – Xi Work/Power P = W/t W = F·d 2 a 2 + b2 = c 2 1.0 kg = 9.81 N x 100 E X A M S O L U T I O N S 1. 2. 3. 4. 5. 6. 7. 8. Suppose a small airplane can fly at 200.0 km/hr compared to the surrounding air. Suppose also that there is a 40.0 km/hr tailwind. How fast does the planes shadow move across the ground? a) 240.0 km/hr b) 200.0 km/hr c) 160.0 km/hr d) 40.0 km/hr P R The Law of Inertia or Newton’s 1 Law states that an object: A a. at rest will remain at rest unless acted on by an outside force. b. will continue moving at the same velocity unless an outside force acts on it. C c. will continue moving in a straight line unless an outside force acts on it. d. that is not moving will never move unless a force acts on it. T e. ALL OF THE ABOVE. When a golf club hits a golf ball, the change in momentum of the ball is _____ the change in the momentum of the club.I a. equal to b. greater than c. less than A freight train rolls along a track with considerable momentum. If it were to roll at the same speed but had twice as C much mass, its momentum would be: E a) zero b)doubled c) quadrupled d) unchanged A boy starts at the flagpole and walks 200.0 ft north. He then turns around and walks 50.0 ft south. What is the boy’s displacement.? a) 250. ft b) 150. ft c) 50.0 ft d) 200. ft st The reason gymnasts train on padded surfaces is that they: a) look nice and feel good under the feet b) increase the force of impact during collisions with the floor c) increase the time of impact during collisions with the floor d) decrease the momentum during collisions with the floor e) decrease the impulse during collisions with the floor The force that would always cause a coasting bicycle to lose speed is: a. gravity b. acceleration c. friction d. mass Alfie the astronaut would have as much trouble pushing open a steel door on a space station as he would on Earth. a) True - the weight of the door is independent of gravity b) False, in zero gravity it is much more easily pushed in space than on the earth c) True - the mass of the door is independent of gravity d) False - steel is much too heavy to use in space E X A M S 9. A student performs a lab in a science class to find out what the velocity of an object traveling across a surface is. She O determines that the object has a velocity of 2.45 m/s. Her teacher tells her that the object actually should have traveled at 2.85 m/s . What is her experimental percentage error closest to? L a) 16% b) 11.6% c) 14% d) 86% U 10. How much force is needed to accelerate a 2.0 kg physics book to an acceleration of 6.0 m/s ? a) 2.0 N b) 6.0 N c) 12 N d) 3.0 N T 11. A moderate force will easily break an egg. However, while an egg dropped on the road usually breaks, one dropped on grass usually does not break. This is because - for the egg dropped on the grass: I a. the change in momentum is greater c. the time interval to stop the egg is greater b. the change in momentum is less d. the time interval to stop the egg is less O 12. A gun fires a bullet. The speed of the bullet will be the same as the speed of the recoiling gun: a. because momentum is conserved b. because velocity is conserved N c. because both velocity and momentum are conserved d. if the mass of the bullet equals the mass of the gun S 13. A rifle recoils from firing a bullet. The speed of the rifle’s recoil is small because the: 2 a) b) c) d) e) force a against the rifle is relatively small impulse on the rifle is less than the impulse on the bullet rifle has a lot more mass than the bullet momentum of the rifle is unchanged none of the above 2 14. A man lifts a 10.0 kg object 2 m. The work he does on the object is: a) 200 J b) 50 J c) 20 J d) 0 J 15. A girl uses a force of 5.0 N to push a box along a floor at constant velocity. The force of friction is: a) 5.0 N b) more than 5.0 N c) less than 5.0 N but not 0 N P R A 17. A man pulls on a 20. kg rock with a horizontal force of 50. N without moving the rock. How much work does the man do on the rock? C a) 9800J b) 1000 J c) 50. J d) 0.0 J 18. A tennis ball and a solid steel ball of the same size are dropped at the same time. Which ball has greater vertical force T acting on it?: a) the tennis ball b) the same force acts on both of them c) the steel ball d) none of these I 19. A swimmer is trying to cross the English Channel from East to West (France to Britain). If the prevailing currents in the C Channel are from South to North, which of the following statements is true: a. The swimmer will end up directly across the Channel from her starting position. E b. The swimmer will end up North of her starting position across the Channel. 16. A job is done slowly, and an identical job is done quickly. Both jobs require the same amount of work but different amounts of : a) energy b) power c) both a and b d) neither a or b c. The swimmer will end up South of her starting position across the Channel. d. The Coriolis Effect will not allow the swimmer to reach the other side. 20. What is ? a. The unit for force. c. The symbol for the coefficient of friction. b. The unit for the coefficient of friction. d. The noise a cow makes. 21. Suppose a gun is made of a strong but very light material. Suppose also that the bullet is more massive than the gun itself. When you observe a person firing this gun at a target: a. the target would be the safest place to stand rather than behind the shooter. b. you see that recoil problems would be lessened with such a gun. c. you know that the momentum of the bullet would be greater than the momentum of the gun. d. you know that the force on the bullet is greater than the force on the gun. E X A M S 23. In the absence of an atmosphere the affect of gravity on falling objects causes O a. heavy objects to fall faster than light objects b. aerodynamic objects to fall faster than bulky or wide objects c. all objects to fall at the same rate d. objects to float L 24. Which of the following cannot be measured in Newtons? U a. The weight of a rock b. The mass of a rock c. The amount of force required to push the rock off the cliff 25. A starship is traveling through empty, interstellar space at constant velocity. It is far from the gravitational effects of T any star or planet. Under these conditions, the force that must be applied to the starship in order to maintain its present velocity is: I a. zero. b. equal to its momentum. c. equal to its mass. d. dependent on how fast it is going. e. equal to its weight O 26. Suppose a cart is being moved by a constant force. If suddenly a load is dumped into the cart so that the cart’s mass N doubles, what happens to the cart’s acceleration? a. It quadruples. b. It doubles. c. It halves. d. It quarters. e. It stays the same. S 27. What is the acceleration and net force on a rocket that is moving directly upward, toward a cloud at constant velocity? 22. From what height must a 225-kg ram of a pile driver have fallen from if it originally had 29550 Joules of energy? a. 13.3 m b. 1.338 m c. 1338.9 m d. 133.8 m a. both acceleration and net force are greater then zero. b. both acceleration and net force are less then zero. c. acceleration is greater then zero, and net force equals zero. d. acceleration is less then zero, and net force greater then zero e. both acceleration and net force equal zero. 3 28. If the spacing on a stretch of ticker tape being pulled by a “Hot Wheels” toy car increases; the car is: a. maintaining constant velocity b. experiencing negative acceleration c. experiencing a positive acceleration d. coming to a stop e. not moving 29. A constant net force acting on an object will cause the object to move with constant: a. speed b. velocity c. acceleration d. momentum 30. Which of the following best illustrates Newton's First Law of Motion? a. a collision between a running back and a linebacker in football b. an ice hockey puck sliding along the ice, AFTER being hit by a players’ stick c. a bowling pin being hit by a bowling ball d. a volleyball being spiked across the net e. all are illustrations of Newton’s 1st law 31. In the absence of air, a penny and a feather dropped from the exact same height: a. fall at different rates b. float c. fall at equal rates d. do not move 32. An object rolling across a surface (neglecting friction) without any horizontal net force acting on it will: a. slow down b. speed up c. keep moving forever d. stop 33. A person sliding into second base continues to slide past the base due to: a. their mass b. the slick surface of the base c. their weight d. gravity 34. Newton's First Law of Motion states that an object at rest stays at rest unless acted upon by: a. a balanced force b. a net force c. a terminal velocity d. a scalar quantity 35. Which of the following is NOT one of Newton's Laws of Motion? a. an object in motion remains in motion unless acted upon by an unbalanced force b. a constant net force acting on an object produces a change in the object's motion c. for every action there is an equal and opposite reaction d. energy is neither created or destroyed; it simply changes form 36. An object falling to Earth in the absence of air resistance: a. falls with a constant acceleration of 9.81 m/s b. falls with a constant acceleration of 9.81 m/s2 c. slows down rapidly d. falls with an uneven rate of acceleration 37. Work is measured in: a. Newtons b. meters per second P R A C T I C E E X A M S 38. The way force, mass, and a change in speed are related is described by the: a. first law of motion b. second law of motion c. third law of motion d. law of conservation of energy O L 39. If you travel a distance of 240 kilometers in 4.0 hours, your speed is: a. 60. km/hr b. 120 km/hr c. 240 km/hr d. 960 km/hr U 40. The name given to the property of all matter that causes the matter to resist a change in its state of motion is: a. gravitation b. friction c. inertia d. kinetic energy T 41. Which of the following would a scientist call work? a. lifting a piece of paper b. reading a notice on the chalkboard c. pushing on a locked door d. studying for a testI 42. On a distance-time graph, what does a straight diagonal line show? O a. changing speed b. acceleration c. constant speed d. time only N 43. How far will you go if you travel 90.0 kilometers per hour, for 2.0 hours? a. 45 kilometers b. 90 kilometers c. 92 kilometers d. 180 kilometers S c. joules per second d. joules 44. Which of the following is a statement of the first law of motion? a. the force acting on an object, the mass of the object, and the resulting speed changes are related. b. An object at rest tends to remain at rest. c. Action force equals reaction force. d. A force of attraction exists between all things. 4 45. Why do objects fall toward the surface of the earth? a. because of gravitational attraction b. because their true resting place is on the surface of the earth c. because air resistance pushes them toward the surface d. because no force acts on falling objects P 46. What was your speed if you traveled 150 kilometers in 2.0 hours? R a. 150 kilometers per hour b. 2 kilometers per hour c. 300 kilometers per hour d. 75 kilometers per hour A 47. Which of the following is true about gravitational attraction? a. it causes objects to reach a terminal speed C b. it is a force between two objects that rub together c. it explains why we don't see the earth move T d. it is a force of attraction between two pieces of matter 48. Before an object will begin to move, the forces acting on that object must: I a. be equal to the force of gravitational attraction b. be equal to the inertia of the object c. become balanced d. become unbalanced C 49. A 30.0 kg object falls through the Earth’s atmosphere and encounters 8.00 N of air resistance. What is the net force E acting on the object as it falls? a. 38.0 N b. 302.0 N c. 22.0 N d. 286 N e. 8.0 N 50. If the distance traveled by a freely falling object were plotted against time, the distance-time graph would be a: a. straight line slanting upward b. a straight line pointing downward c. level (no slope) line d. curved line, curving upward 51. How much work is done if a force of 20.0 Newtons is used to move an object 5.00 meters? a. 20.0 joules b. 4.00 joules c. 25.0 joules d. 100. joules 52. What kind of energy does a stretched rubber band have? a. radiant b. kinetic c. potential d. gravitational potential 53. What kind of energy does a moving automobile have as a result of its motion? a. radiant b. kinetic c. potential d. gravitational potential E X A M S O L 55. Potential energy changes to kinetic energy as: a. you stretch a rubber band b. you raise a box to a high shelf c. a rock falls from a cliff d. a moving car stopsU 56. If you push a heavy object but do not make it move, you have: T a. done work b. used a lot of power c. done no work d. increased your potential energy I 57. Friction: a. increases motion b. opposes motion c. has no effect on motion d. is created in a vacuum only O 58. A falling ball thrown from the top of a building would be said to have accelerated motion because it would: a. follow a straight path b. fall with a constant speed N c. strike the ground with a certain force d. increase its speed during each second it is falling S 59. The magnitude of the force of gravity acting on a particular object is called its: 54. What facts would you have to know in order to find out how much work had been done on an object? a. the amount of force used and how long it takes to do the work b. The distance the object moved and how long it took to move it c. The amount of force used and the distance the object moved d. The amount of energy used and how long the energy was used a. acceleration b. weight c. speed d. mass 60. By rule of the law of conservation of energy when a books falls from your book bag to the floor: a. some energy is created b. some energy is lost c. energy was changed from one form to another d. there was no change in the form of energy 5 61. Air resistance is an example of: a. kinetic energy b. friction c. momentum d. Law of the Conservation of Mass 62. A pole vaulter needs to maximize the velocity (running) she attains before vaulting because increasing her KE will: a. increase her downward gravitational force b. decrease the potential energy of the height c. increase the potential energy of her motion d. increase the potential energy in the bend of the pole P R 63. A Scalar Quantity is a quantity that can be described bya. the skin of a fish or reptile b. a magnitude value A c. a magnitude and direction value d. velocity and acceleration 64. While trying to escape a classroom after a particularly bad lecture, a group of students place 125.0 N of force on a door C to push it open. At the same time the instructor tries to keep them in class by placing 251.0 N on the door - in the opposite direction. What is the net force being placed on the door? T a. 376.0 N b. 126.0 N c. 0.00 N d. 31375.0 N I 65. A car travels with its cruise control set to 97.0 km/hr. It travels a distance of 256 km. How long did it take to cover the distance? C a. 26.4 hours b. .379 hours c. 24,832 seconds d. 2.64 hours E 66. A man runs at a speed of 2.50 m/s. He runs for 1.50 hours. How far does he go? a. 13,500 m b. 13.5 m c. 13, 500 km d. 2160 m E 68. A baseball catcher throws a ball vertically upward and catches it in the same spot as it returns to the mitt. At what point in X the ball’s path does it experience zero velocity and nonzero acceleration at the same time? a. midway on the way up A b. at the top of its path c. the instant it leaves the catcher’s hand M d. the instant before it arrives in the catcher’s mitt 67. As an object falls freely in a vacuum (that is created on the earth) its: a. velocity increases b. acceleration increases c. both a and b d. None of these 69. When you push against a wall while sitting on a scooter, the action and reaction forces are “balanced” but do not cancel each other out because: a. the action-reaction forces are equal and opposite but not all the time b. the action-reaction forces are not truly equal and opposite forces under normal conditions c. the action-reaction forces are acting on two different objects d. the wall’s force actually ends up larger than the your force – under normal conditions. S O 70. A ping-pong ball and a solid steel ball of the same size are dropped at the same time. In the absence of air resistance, L which ball has a greater acceleration? a. they both have the same acceleration b. the steel ball U c. the ping-pong ball d. impossible to answer with the information given T 71. An object can maintain its state of motion because it has: a. a mass b. an acceleration c. a velocity d. all of these I 72. In the absence of air resistance, the vertical component of a projectile’s velocity does not change as the projectile moves. This statement is: O a. always true b. sometimes true c. always false d. sometimes false 73. The engine of a drag-racing car produces a thrust of 1500 N. If the car runs down a drag-strip for five seconds what isN the impulse applied to the car? S a. 7.500 kg·m/s b. 300 N·s c. 7500 N·s d. 300 kg m/s 2 74. When you put on the brakes of a car, friction causes some of the mechanical energy (KE + PE) of the car to be converted into_____. a. more mechanical energy b. kinetic energy c. potential energy d. thermal energy (heat) 6 75. A car moves from rest to 10.0 m/s in 12.5 seconds. What distance does the car travel during this time? a. 5 m b. 62.5 m c. .8 m d. 125 m 76. What amount of net force has to be applied to a object with a weight of 188 N to accelerate it at 5.30 m/s2? a. 996.4 kg m/s b. 35.4 N c. 101.7 N d. 102 N P 77. Tarzan can swim at a speed of 5.00 km/hr in still water. How long will it take him to swim 8.00 km upstream if the R current against him is 2.00 km/hr? A a. 1.14 hours b. .375 hours c. 2.67 hours d. 24 hours 78. If you constantly exert a horizontal force of 200 N to slide a crate across a factory floor at a constant velocity, how much C friction is exerted by the floor on the crate? a. Zero T b. 200N c. 200 N divided by the mass of the crate. I d. 200 N times the acceleration of gravity. e. 200 N times the acceleration of gravity and divided by the mass of the crate. C 79. The tape from the ticker tape “spark” timer is used to accurately measure: a. distance b. time c. velocity d. acceleration e. all of these E 80. Forces of 30.0 N and 25.0 N in the same direction act on an object. What was the net force on the object? a. 750.0 N b. 55.0 N c. 0.0 N d. 5.0 N 81. The independent variable is: a. the observed variable in an experiment b. the variable that is uncontrolled (but can be manipulated) by the experimenter c. always the variable that has no effect in an experiment d. the variable that shows the greatest difference in the experiment 82. A softball with a mass of .200 kg is moving at 3.0 m/s before it collides head-on with a stationary .150 kg baseball. After the collision, the baseball is moving forward at a speed of 2.5 m/s. How fast is the softball moving after the collision? a. 0.333 m/s b. 25.0 m/s c. 1.13 m/s d. 4.00 m/s E X A M S O L 84. What is the speed of an object that covers a distance of 23.0 meters in 5.4 seconds a. 4.3 m/s b. 124.2 m/s c. .235 m/s d. 43 m/s U 85. What distance does an object go if it has a speed of 3.200 m/s for 34.00 seconds? T a. 10.60 meters b. 0.940 meters c. 108.8 meters d. 106.0 meters 86. A car slows from 45.0 m/s to 38.0 m/s in 4.00 seconds to avoid hitting a pot-hole. What was the acceleration of the car I as it decreased its speed? a. 1.75 m/s b. 49.25 m/s c. – 1.75 m/s d. – 49.25 m/s O 87. A cyclist at 0.00 m/s increases her speed to 13.0 m/s over the first minute of a race. What was her N acceleration? a. 0.22 m/s b. 13 m/s c. −0.21 m/s d. – 13 m/s S 83. A 45.0-kilogram bag of cement mysteriously falls from a construction platform that Mr. Kedge was working on to the ground 18.5 meters below where Mr. Lopez was sleeping on a park bench. What amount of energy did it strike the ground with? a. 8166 J b. 8170 J c. 8166.8 J d. 30775 J 2 2 2 2 2 2 2 2 88. What distance does a cyclist cover if she has an acceleration of 1.20 m/s 2 over the first 90.0 seconds of a race? a. 54.0 m b. 4860 m c. 108 m d. 9720 m 7 Data for questions 89 – 91: A man ran a 20.0 meter sprint. Times were recorded at every 5.0 meter interval as he ran. The following table shows the total time it took to reach each 5.0 meter interval. It took him a total of 4.2 seconds to cover the entire 20.0 meter distance. Mr. Fastie Distance Intervals (m) 0.0 m 5.0 m 10.0 m 15.0 m 20.0 m Total time to reach each interval (s) 0.0 s 1.7 s 2.7 s 3.3 s 4.2 s 89. During which interval (0-5, 5-10, 10-15 or 15-20) did he record his highest speed? a. the 0-5 m interval b. the 5-10 m interval c. the 10-15 m interval d. the 15-20 m interval 90. What was the speed during his fastest interval? a. 5.0 m/s b. 8.3 m/s c. 7.1 m/s d. 3.1 m/s 91. To describe the person’s total dash in terms of speed during distance intervals, you could say: a. He started fast and gradually slowed through the finish. b. He started slow, gained speed then faded toward the end. c. He began slowly and gradually sped up through the finish d. He began fast, slowed down, then gained speed to finish P R A C T I C E 92. According to Newton’s second law, when the same force is applied to two objects of different masses: a. the object with greater mass will experience a great acceleration, and the object with less mass will experience an even greater acceleration. b. the object with greater mass will experience a smaller acceleration, and the object with less mass will experience a greater acceleration. c. the object with greater mass will experience a greater acceleration, and the object with less mass will experience a smaller acceleration. d. the object with greater mass will experience a small acceleration, and the object with less mass will experience an even smaller acceleration. E X A M 93. The force that opposes motion: a. inertia b. displacement S O L U T I O N S 94. The capacity to do work: a. momentum b. inertia c. gravity d. friction c. energy 95. The curved path that an object thrown into the air will follow: a. projectile b. trajectory c. range d. acceleration d. vector 96. Forces acting on a single object that are equal in size but opposite in direction: a. projectile b. net c. displaced d. balanced 97. Newton’s First law of motion states a. Energy cannot be created or destroyed, it can only be converted from one form to another. b. An object in motion remains in motion unless acted upon by outside forces. c. A force is required to cause an object to accelerate in the direction the force is applied. d. In order work to be accomplished, a force must be applied over a distance. 98. A large truck sits on a street – full of furniture. A police car speeds past the truck at 50.0 m/s. Which vehicle has the greater inertia? a. the police car because of the speed at which it is moving b. neither because the forces acting on them are equal and opposite – of course c. the Truck because it has a greater mass than the car. d. The police car because it has a greater acceleration than the Truck, which is standing still 8 99. A person standing on a 50.0 m high cliff throws a Kedge out horizontally with an initial speed of 10.0 m/s. At the same instant, from the same height, he drops a Lopez off of the cliff. Which would hit the ground first? (neglecting air resistance, of course) a. the Kedge will hit first because it is “more aerodynamic” b. they will both hit the ground at the same time. c. the Lopez will hit first because it is “dense” and thus has more mass than the Kedge d. the Kedge will land farther away from the cliff than the Lopez will. P R 100. An object covers a distance of 20.0 meters at a speed of 3.00 m/s. How much time did it take? A a. .150 seconds b. 60 seconds c. 15.0 seconds d. 6.67 seconds 101. A car accelerates at 1.75 m/s over a time period of 4.00 seconds. Its initial velocity was 0.00 m/s. What was its finalC velocity? a. 4.40 m/s b. 2.30 m/s c. 7.00 m/s d. 1.75 m/s T 102. A gargoyle falls from the ledge of a tall building it hits the ground 7.00 seconds later. How far did it fall? I a. 34.3 m b. 240 m c. 480 m d. 49 m C 103. What was the speed of the gargoyle, in the previous question, just before it hit? a. 68.7 m/s b. 4.9 m/s c. 1.40 m/s d. 35.0 m/s E 104. How much force is needed to accelerate a 78.0 kg box at 4.00 m/s ? 2 2 a. 19.5 N b. 312 N c. .051 N d. .312 N E X 106. A person pushes a 56.0 kg frictionless cart down an incline at a rate of 2.50 m/s. How much kinetic energy does the cart have? A a. 175 J b. 70 J c. 140 J d. 350 J M 107. How much work is done if a person uses a force of 50.0 N to push a 100.0 kg box a distance of 3.00 meters? 105. An 86.0 kg diver plans to jump off of a 35.0 meter platform into a pool of water. Using GPE = mgh, calculate the gravitational potential energy of the diver. a. 29528 J b. 29530 J c. 29500 J d. 30000 J a. 16.7 J b. .060 J c. 225 J d. 150. J 108. How much power is used if the person in the previous question took 3.40 seconds to push the box the 3.00 meters? a. 44.1 N b. 44.1 W c. 450 W d. 0.02 J 109. If a force applied to an object is doubled what would happen to the object’s acceleration. a. It also would double. c. It would remain the same. b. it would be cut in half d. it would be squared 110. A person has a weight of 176 pounds. What is their weight in Newtons? a. 800 N b. 80 N c. 784 N d. 80 kg 111. Which of the following would have the most potential energy and the least kinetic energy? a. you riding a bike on level ground b. you on a bike at the top of a hill, not moving c. you riding a bike down a hill d. you on a bike at the bottom of a hill, not moving 112. Which of the following is a vector quantity? a. your speed b. your mass c. your acceleration 113. Which of the following is measured in Joules? a. PE b. KE c. Work d. All of the above d. all of the above 114. A child with a mass of 35 kg is on a sled with a mass of 5.0 kg. If the child and the sled traveling together have a kinetic energy of 2600 J, How fast are they moving? a. 130 m/s b. 11 m/s c. 11 m/s2 d. Unable to determine the speed from the information given 9 S O L U T I O N S 115. When a force is exerted on an object, work is done only if the object a. is heavy b. remains stationary c. moves d. has no momentum 116. The momentum of an object can be calculated by multiplying the mass by the a. acceleration b. velocity c. impulse d. time 117. A large 6.0 kg fish swims at a rate of 1.0 m/s to the left. An unsuspecting 2.0 kg fish swims to the right directly toward the larger fish at a rate of 2.0 m/s. What is the velocity and direction of the larger fish after it consumes the smaller fish? a. .25 m/s to the left b. 4.0 m/s to the left c. 0.00 m/s – they come to a dead stop d. .25 m/s to the right 118. The horizontal acceleration of a projectile ____ as its position changes. a. Increases b. decreases c. is constant 119. Mass and weight are related by a. the acceleration due to gravity b. Newtons d. is zero c. friction d. inertia 120. You would have the largest mass of gold if your chunk of gold weighed 1 N on: a. the Moon (about 1/6 the gravity of Earth) b. Earth c. Jupiter (about 2.5x the gravity of Earth) 121. The chart at the right is a record of the masses and times of students coasting down a hill on a bike. From the data one can logically conclude that: a. the hill is not very steep. b. mass and time are inversely related c. mass and time are directly related d. time does not depend on mass e. lighter people accelerate more than heavier people. MASS (kg) 50 55 60 65 70 TIME (s) .44 .50 .48 .52 .41 P R A C T I C E E X A M S O L 123. Convert .730 km to m. U a. 0.000730 m b. 0.730 m c. 7.30 m d. 730. m e. 73,000 m T 124. There are two identical, 2 kg blocks. Both are initially at rest. A net force of 8 N pushes on the first block for 4 seconds. A net force of 10 N pushes on the second block for 3 seconds. In the absence of friction which block will have I the greater final speed? a. the first block. O b. the second block. c. the final speed of both blocks will be zero m/s. d. the final speed of both blocks will be the same (but greater then zero m/s). N 125. A large massive truck and a small compact car roll down a hill. If friction is negligible, which will reach the bottom of S the hill first? 122. Two vectors are the same if: a. They point in the same direction but do not have the same size. b. Same magnitude but not size c. Same size and direction d. Same direction but not the same size e. Different magnitude but same direction. a. b. c. d. The car will reach the ground first since it feels the effects of air resistance less than the massive truck. The truck will reach the ground first since it is more massive, it will not be slowed down by friction. They will both reach the ground at the same time since all objects accelerate (due to gravity) at an equal rate in the absence of friction. Both objects will move at a constant velocity down the hill reaching the bottom at the same time. 10 Questions #126 -#128 refer to the graph below – the below graph depicts the motion of a cat 126. According to the graph above, during which interval is the cat at rest? a. 0.0–5.0 s b. 5.0–10.0 s c. 10.0–15.0 s d. 15.0–20.0 s 127. According to the graph above, the cat has the fastest speed during which interval? a. 0.0–5.0 s b. 5.0–10.0 s c. 10.0–15.0 s d. 15.0–20.0 s 128. According to the graph above, during which interval does the cat have the greatest positive velocity? a. 0.0–5.0 s b. 5.0–10.0 s c. 10.0–15.0 s d. 15.0–20.0 s Significant Figures: Review your rules Determine the number of significant figures in each of the following measurements; 503 m ____3_____ 0.0015 mg ____2_____ 635.526 g ____6_____ 630 ml ____2____ 601L ____3_____ 10001 m ____5_____ 2407 g ____4_____ 500 ml ____1_____ 1.0000006 µg ____8_____ Assume all of the following are measurements 129. Multiply (2.3 x 103) and (3.43 x 104) a. 7.889 x 107 b. 8 x 101 130. Divide (4.5 x 108 ) a. 2.64 x 105 c. 7.89 x 107 by (1.7 x 103) b. 3 x 105 c. 2.6 x 105 131. Add (3.75 x 104) and (6.1 x 105) a. 64.75 x 104 b. 6 x 105 d. 2.647 x 105 c. 6.475 x 105 d. 6.5 x 105 132. Subtract (2.20 x 107) from (4.4 x 107) a. –2.2 x 107 b. 6.6 x 107 c. 2.2 x 107 d. 2 x 107 133. Add the following ( 23.334 + 13.00 + 0.00234 ) a. 36.34 b. 36.3 c. 36.336 134. Multiply the following : ( 23.098 a. 70.0 b. 70.1 x d. 7.9 x 107 3.033 x c. 70.056 d. 36.33634 1.0 ) d. 70. 135. Subtract the following: ( 31.1 – 5.456 – .00981 – 4.0 ) a. 21 b. 22 c. 21.6 d. 21.634 136. Divide the following: ( 23.045 ÷ 1.34 ÷ .12 ) 11 e. 70 P R A C T I C E E X A M S O L U T I O N S a. 143.3 b. 140 c. 143.31 d. 143 137. Speed is: a. a measure of how fast something is moving c. always measured in terms of a unit of distance divided by time b. the distance covered per unit time d. all of these P R 139. Whenever an object exerts a force on another object, the second object exerts a force of the same magnitude, A but in the opposite direction to that of the first object. This is: a. always true b. sometimes true – depending on the masses of the objects C c. always false d. sometimes false – depending on the velocities T 140. A tablecloth can be quickly withdrawn from under a place setting without the place setting crashing to the floor. The reason this can be done because: I a. the place setting has very little weight b. there is an action/reaction pair on the items c. gravity pulls very hard on the place setting d. of the inertia of the place setting C 141. Which has more momentum, a bowling ball dropped from a 10.0 m high ledge or a basketball dropped from the same ledge? Neglecting air resistance – of course. E a. the bowling ball 138. If you lift two 10.0 kg loads up one story, how much work do you do compared to lifting just one 10.0 kg load up one story? a. 4x as much b. 2x as much c. same amount d. 1/2 as much e. 1/4 as much b. c. d. the basketball neither, the momentums would cancel each other out in the absence of air resistance, they would both have the same momentum 142. Accelerations are produced by: a. velocities b. momentums c. forces d. inertias 143. A vector quantity is one that has: a. magnitude and time b. magnitude and direction c. direction only e. all of these d. magnitude only 144. When you look at the speedometer of a car, you see the car’s: a. average speed b. instantaneous acceleration c. constant speed d. instantaneous speed e. average distance E X A M S O 145. How does acceleration of an object change in relation to its mass? It is ____: L a. directly proportional b inversely proportional c. acceleration does not depend on mass 146. If the momentum of an object changes and its mass remains constant: U a. its velocity is changing b. it is accelerating either positively or negatively c. there is a force acting on it d. all of the above T 147. If you push an object with twice the force for twice the distance, you do: I a. the same work b. twice the work c. four times the work d. eight times the work 148. An archer shoots an arrow. Consider the action force to be the bow-string against the arrow. The reaction force is the: O a. weight of the arrow N b. air resistance against the bow c. friction of the ground against the archer’s feet d. grip of the archer’s hand on the bow S e. the arrow’s push against the bow string 149. Objects A and B sit at rest on level ground. Object A has twice as much mass as object B giving it twice as much: a. inertia b. momentum c. gravitational potential energy d. energy e all of the above 12 150. A 6.0 kg fish swims toward a stationary 2.0 kg fish. If the larger fish initially swims at a rate of 1.0 m/s, what is the velocity of the large fish shortly after is consumes the smaller fish? a. 0.0 m/s – they come to a dead stop b. 0.75 m/s in the same direction c. 0.25 in the opposite direction d. 6.0 m/s in the same direction 151. The greatest change in momentum will be produced by a a. large force acting over a long time c. large force acting over a short time b. a small force acting over a short time d. no force at all is needed 152. Qualitative measurements are those that: a. use numbers and units to describe and object b. deal only with the International System of units c. do not use numbers or units to describe objects d. deal only with the English system of measurement 153. What would be the resultant when adding the following vectors? a. b. + c. d. 154. An object following a straight line path at a constant speed: a. has a net force acting on it in the direction of the motion b. has zero acceleration c. has no forces acting on it d. must be moving in a vacuum e. None of the above 155. Potential energy is the energy an object has because of its: a. speed b. location c. size d. temperature E X A M e. density Analyze these ticker tapes. Describe what is happening to the hot-wheels car in each case. 156. 157. 158. 159. 13 P R A C T I C E S O L U T I O N S 160. A car begins at rest – increases its speed to 10.0 m/s - maintains that speed for a time – slows down – comes to a complete stop. When the car slows down, the cork in the cork accelerometer will: a. drift back in the direction opposite motion b. remain straight up and down c. drift forward in the direction of motion d. bob back and forth 161. In order to increase the momentum of a hockey puck, we could: a. increase the force acting on the puck b. increase the time of contact with the puck c. follow through when hitting the puck d. swing as hard as possible e. all of the above 162. In terms of acceleration, what exactly does 2.0 m/s2 mean? a. an object has a speed of 2 m/s for two seconds of motion b. an object accelerates from 0 m/s to 2 m/s in two seconds c. an object reaches an acceleration of 2 m/s after two seconds d. an object accelerates 2m/s for every second of motion P R A C T I C E 163. A cart is being moved by a force. If a load is suddenly dropped in the cart so that its mass doubles, what happens to the cart’s acceleration? a. the acceleration quadruples b. the acceleration doubles c. the acceleration is cut in half d. the acceleration remains constant E X 164. A ball is thrown upwards and caught when it comes back down. In the absence of air resistance, the speed of the ball A when caught would be: a. more than the speed it had when thrown upwards M b. less than the speed it had when thrown upwards c. d. the same as the speed it had when thrown upwards exactly half of the speed it had when thrown upwards S O 166. A garbage truck and a small car traveling at the same speed have a head-on collision. The vehicle to undergo the greater L change in velocity is the: a. the small car b. the garbage truck c. both the same d. both cancel each other out U 167. Kedge is standing on a completely frictionless frozen pond. In order to get off of the ice, he should: a. walk very slowly on his tiptoes T b. bend over touching the ice in front of him, then bring his feet to his hands c. throw something in the direction opposite to that in which he wants to go. I d. get on his knees and pray for Lopez to bail him out once again. e. a, b and c would all work. O 168. Energy can be transformed from one form to another with no loss or gain of energy. This is: a. always true b. sometimes true c. always false d. true only when momentum is conserved N 169. As a pendulum swings back and forth: S 165. A rock has a weight of 1.0 N. The net force on the rock when it is in free-fall (neglecting air resistance) is: a. 0.0 N b. 0.10 N c. 1.0 N d. 9.8 N d. none of these a. b. c. d. e. potential energy is transformed into kinetic energy kinetic energy is transformed into potential energy at the lowest part of the swing the energy is all kinetic at the end points of the swing, the energy is all potential all of the above 14 170. As a basketball player starts to jump for a rebound, the player begins to move upward faster and faster until his shoes leave the floor. At the moment the player begins to jump, the force of the floor on the shoes is a. greater than the player’s weight b. equal in magnitude and opposite in direction to the player’s weight. c. less than the player’s weight. d. zero. P R 171. Two objects, A and B, have the same size and shape, but A has twice the mass of B. They are both dropped simultaneously from a tower. They reach the ground at the same time, but A has a higher: a. speed b. acceleration c. momentum d. all of these e. none of these A 172. Two skaters stand facing each other. One skater’s mass is 60 kg, and the other’s mass is 72 kg. If the skaters push awayC from each other without spinning, a. the lighter skater has less momentum. T b. their momentums are equal but opposite. c. their total momentum doubles. I d. their total momentum decreases. C 173. Kedge pushes a huge shipping crate with a force of 52.0 N in one direction. Lopez pushes the same crate in the opposite direction with a force of 66.0 N. What is the net force on the crate? a. 118 N b. 1.26 N c. 14.0 N d. not enough information to determine E 174. The weight of a person can be represented by a vector that acts: a. perpendicular to the ground underneath the person b. parallel to the ground c. in a direction that depends on where the person is standing d. always straight downward, even if the person stands on a hill e. all of the above 175. A martial arts expert executes a swift blow and breaks a block of ice in two with her bare hand. a. the impulse on both the block and the expert’s hand have the same magnitude b. the force on both the block and the expert’s hand have the same magnitude c. the time of impact on both the block and the expert’s hand is the same d. all of the above e. none of the above E X A M S O 177. A net horizontal force of 5.00 N acts upon a 4.00 kg object that is already moving along at 9.00 m/s. The net force actsL on the object for 11.0 seconds. What is the final velocity of the object? a. 55.0 m/s b. 9.00 m/s c. 13.7 m/s d. 22.8 m/s U 178. An object is traveling along with a velocity of 3.94 m/s. What is its mass if a force of 5.40 N applied for a time period T of 6.83 s accelerates it to a velocity of 19.09 m/s? a. 36.88 kg b. 1.33 kg c. 3.16 kg d. 0.411 kg e. 2.43 kg I 179. In order to increase the final momentum of a golf ball, we could O a. increase the force acting on it. b. follow through when hitting the ball. N c. increase the time of contact with the ball. d. swing as hard as possible. e. all of the above S 176. A force acts upon a 2011 N truck. The force decreases its speed from 10.0 m/s to 5.00 m/s in 6.00 sec. What is the magnitude of the force? a. 171 N b. -171 N c. 6120 N d. 2040 N 180. Identify the following as scalar or vector: the speed of a snail, the time it takes to run a mile, free-fall acceleration. a. vector, scalar, scalar b. vector, scalar, vector c. scalar, scalar, vector d. scalar, vector, vector 15 181. When a basketball player jumps to make a shot, once the feet are off the floor, the jumper's acceleration a. varies with body orientation. b. depends on launch speed. c. is usually greater for taller players (but not always). d. depends on all the above. e. is 9.81m/s2; no more, no less. P R 182. What is the impulse on an object if its momentum changes from 12.6 kg-m/s to 22.7 kg-m/s? A a. 10.1 N·s b. 35.5 N·s c. 264 N·s d. 1.79 N·s C 183. An object has a momentum of 15.4 kg-m/s. An impulse acts upon it, changing its momentum by 44.2 kg-m/s. What is the final momentum for this object? T a. 59.6 kg-m/s b. 28.8 kg-m/s c. 2.86 kg-m/s d. 681 kg-m/s I 184. According to the scientific method, why does a physicist make observations and collect data? a. to decide which parts of a problem are important C b. to ask a question c. to make a conclusion d. to solve all problems E 185. If some measurements agree closely with each other but differ widely from the actual value, these measurements are a. neither precise nor accurate. b. accurate but not precise. c. acceptable as a new standard of accuracy. d. precise but not accurate. 186. When there is no air resistance, objects of different masses a. fall with equal accelerations with similar displacements. b. fall with different accelerations with different displacements. c. fall with equal accelerations with different displacements. d. fall with different accelerations with similar displacements. 187. Identify the following quantities as scalar or vector: the mass of an object - the number of leaves on a tree - the wind velocity. a. vector, scalar, scalar c. scalar, vector, scalar b. scalar, scalar, vector d. vector, scalar, vector E X A M S O 188. Which of the following is an example of projectile motion? L a. a jet lifting off a runway b. a bullet that has been fired from a gun c. dropping an aluminum can into the recycling bin U d. a space shuttle orbiting Earth T 189. If the only force acting on an object is friction during a given physical process, which of the following assumptions must be made in regard to the object’s kinetic energy? I a. The kinetic energy decreases. b. The kinetic energy increases. O c. The kinetic energy remains constant. d. The kinetic energy decreases and then increases. N 190. Which of the following statements is not true? a. Science is a method of answering theoretical questions. S b. c. d. e. Technology is a method of solving practical problems. Technology may produce problems for society. Science and technology make up a large part of everyday lives A good scientist is influenced by his or her likes and dislikes. 16 191. The difference between a hypothesis and a theory is that a hypothesis is a. never true whereas a theory is always true. b. true whereas a theory is not true. c. an isolated fact whereas a theory is a huge collections of facts d. never true whereas a theory is sometimes true e. an educated guess whereas a theory has been tested successfully many times in many ways. 192. Suppose an object is in free fall. Each second the object falls : a. the same distance as in the second before. b. a larger distance than in the second before c. with the same instantaneous speed. d. with the same average speed. e. none of the above 193. A car traveling along the highway needs a certain amount of force exerted on it to stop. More stopping force may be required when the car has: a. less stopping distance. b. more momentum. c. more mass. d. all of the above e. none of the above 194. Which of the following is a physical quantity that has a magnitude but no direction? a. vector b. resultant c. scalar d. frame of reference P R A C T I C E 195. At what point of the ball’s path shown in the figure above is the vertical component of the ball’s velocity zero? a. A b. C c. B d. D E X A M 196. In the figure above, the magnitude of the ball’s velocity is least at location a. A. b. B c. C. d. D. The figure to the right shows the path of a ball tossed from a building. Air resistance is ignored. Use the figure to answer questions 195 – 199. 197. In the figure above, the magnitude of the ball’s velocity is greatest at location a. A b. B c. C d. D 198. In the figure above, the horizontal component of the ball’s velocity at A is a. zero b. equal to the vertical component of the ball’s velocity at C. c. equal in magnitude but opposite in direction to the horizontal component of the ball’s velocity at D. d. equal to the horizontal component of its initial velocity. 199. In the figure above, at which point is the ball’s speed about equal to the speed at which it was tossed? a. A b. B c. C d. D 200. A boat that goes 4.50 km/hr in still water moves directly east across a river that is flowing at 7.50 km/hr to the north. What is the resulting velocity of the boat? a. 8.74 km/hr b. 12.0 km/hr c. 76.5 km/hr d. 3.00 km/hr 201. A car is driven 15.0 kilometers north down a street turns and goes 3.50 kilometers west until it runs out of gas and stops. What is the resulting displacement of the car? a. 18.5 km b. 237 km c. 11.5 km d. 15.4 km **DO NOT DEPEND ENTIRELY ON THIS PRACTICE TEST FOR YOUR PREPARATION** 17 S O L U T I O N S