Download Midterm Exam Study Guide

Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
Midterm Exam Study Guide (Chapters 2 – 8)
Respond to each of the following items in preparation for your Midterm Exam and use this packet as your study guide.
Turn this assignment in on the day of your exam. It will count as a homework grade.
Multiple Choice
Identify the choice that best completes the statement or answers the question. Write your response on the space provided.
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1. A train travels 6 meters in the first second of travel, another 6 meters in the second second of travel, and 6
meters again during the third second. Its acceleration is _____.
a. 0 m/s2
c. 12 m/s2
2
b. 6 m/s
d. 18 m/s2
2. A car starts from rest and after 7 seconds, it is moving at 42 m/s. What is the car’s average acceleration?
a. 0.17 m/s2
c. 6 m/s2
2
b. 1.67 m/s
d. 7 m/s2
3. As an object falls freely in a vacuum, its _____.
a. velocity increases
c. both (a) and (b)
b. acceleration increases
d. none of the above
4. In the absence of air resistance, objects fall at constant _____.
a. speed
c. acceleration
b. velocity
d. distances each successive second
5. A ball is thrown upwards and caught at the same height as it comes back down. In the absence of air
resistance, the speed of the ball just before it is caught would be _____.
a. less than the speed it had when thrown upwards
b. more than the speed it had when thrown upwards
c. the same speed it had when thrown upwards
d. 0 m/s
6. 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
7. A ball tossed vertically upwards rises, reaches its highest point, and then falls back to its starting point.
During this time, the acceleration of the ball is always _____.
a. in the direction of the motion
c. directed downward
b. opposite its velocity
d. directed upward
8. When a basketball player jumps, once the feet are off the floor, the jumper’s acceleration _____.
a. varies with body orientation
c. is usually greater for taller players
b. depends on launch speed
d. is always equal to g
9. Suppose you take a trip that covers 180 km and takes 3 hours to make. Your average speed is _____.
a. 30 km/h
c. 180 km/h
b. 60 km/h
d. 360 km/h
10. When an object falls to the ground, it accelerates. This acceleration is called the acceleration due to gravity
and is symbolized by the letter g. What is the value of g on the Earth’s surface?
a. 0 m/s2
c. about 10 m/s2
2
b. about 5 m/s
d. about 98 m/s2
11. A car accelerates at 2 m/s2. Assuming the car started from rest, how much time will it need to accelerate to a
speed of 20 m/s?
a. 2 seconds
c. 20 seconds
b. 10 seconds
d. 40 seconds
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
____ 12. If a ball were equipped with a speedometer and allowed to fall freely on a planet where the acceleration due to
gravity is 23 m/s2, the reading on the speedometer would increase by _____ each second.
a. about 10 m/s
c. 11.5 m/s
b. 9.8 m/s
d. 23 m/s
____ 13. A freely falling object starts from rest. After falling for 6 seconds, it will have a speed of about _____.
a. 6 m/s
c. 16 m/s
b. 60 m/s
d. 600 m/s
____ 14. If a projectile is fired straight up at a speed of 30 m/s, the total time to return to its starting point is about
_____.
a. 3 seconds
c. 10 seconds
b. 6 seconds
d. none of the above
____ 15. Suppose a basketball player claims she has a hangtime of 2 seconds! This would mean she has a vertical leap
of almost _____.
a. 5 m
c. 3 m
b. 4 m
d. 2 m
____ 16. A scalar is a quantity that has _____.
a. magnitude and time
c. time a direction
b. magnitude and direction
d. only a magnitude
____ 17. In order to find the components of a vector, you should _____.
a. draw the vector with the correct magnitude and orientation
b. measure the sides of the right triangle
c. draw a right triangle so that the vector is the hypotenuse
d. all of the above
____ 18. In the absence of air resistance, the angle at which a thrown ball will go the farthest is _____.
a. 15°
c. 45°
b. 30°
d. 60°
____ 19. A ball thrown in the air will never go as far as physics ideally would predict because _____.
a. the ball would never land
c. air resistance slows the ball
b. gravity is acting on it
d. all of the above
____ 20. A cannonball is launched from the ground at 30 m/s at an angle of 30° above the horizontal. Ignoring air
resistance, the ball with hit the ground with a speed of _____.
a. 0 m/s
c. 30 m/s
b. 20 m/s
d. 9.8 m/s2
____ 21. A projectile launched horizontally hits the ground in 0.8 seconds. If it had been launched with twice the
speed in the same direction, it would have hit the ground in _____.
a. less than 0.8 s
b. twice the amount of time
c. more than 0.8 s
d. 0.8 s
____ 22. An object is dropped and falls freely to the ground with an acceleration of g. If it thrown upward at an angle
instead, its acceleration would be _____
a. less than g
c. g
b. more than g
d. zero
____ 23. Which best approximates the resultant of a pair of 6-unit vectors perpendicular to each other?
a. 0 units
c. 8 units
b. 6 units
d. 12 units
____ 24. Which best approximates the resultant of a pair of 6-unit vectors parallel to each other?
a. 0 units
c. 8 units
b. 6 units
d. 12 units
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
____ 25. What is the resultant of a 3-unit vector and a 4-unit vector at right angles to each other?
a. 1 units
c. 7 units
b. 5 units
d. none of the above
____ 26. When in orbit, a satellite such as the Hubble telescope or the moon is _____.
a. simply a projectile
c. free from Earth’s gravity
b. not acceleration
d. moving with constant velocity
____ 27. Suppose a small plane can fly at 170 km/h and that there is a tailwind of 60 km/h. How fast does the plane’s
shadow move across the ground?
a. 110 km/h
c. 185 km/h
b. 170 km/h
d. 230 km/h
____ 28. Ignoring air resistance, at what other angle will a thrown ball go the same distance as one thrown at an angle
of 75°?
a. 15°
c. 80°
b. 65°
d. 90°
____ 29. Ignoring air resistance, at what other angle will a thrown ball go the same distance as one thrown at an angle
of 10°?
a. 15°
c. 80°
b. 65°
d. 90°
____ 30. When calculating the resultant of two vectors pointed in opposite directions, _____.
a. the magnitudes should be added
c. the magnitudes should be multiplied
b. the magnitudes should be subtracted
d. use the Pythagorean theorem
____ 31. The astronomer Copernicus publicly stated in the 1500s that Earth _____.
a. does not move
c. is slowing down
b. revolves around the sun
d. is the center of the solar system
____ 32. The law of inertia states that an object _____.
a. will continue moving at the same velocity unless an outside force acts on it
b. will continue moving in a straight line unless an outside force acts on it
c. at rest will remain at rest unless acted on by an outside force
d. all of the above
____ 33. If the force of gravity suddenly stopped acting on the planets, they would _____.
a. spiral slowly away toward the sun
b. continue to orbit the sun
c. move in a straight lines tangent to their orbits
d. fly straight away from the sun
____ 34. One object has twice as mass as another object. The first object also has twice as much _____.
a. velocity
c. inertia
b. gravitational acceleration
d. all of the above
____ 35. Compared to its weight on Earth, a 10 kg object on the moon will weigh _____.
a. the same
c. less
b. more
d. 6 times the amount
____ 36. Compared to its mass on Earth, the mass of a 10 kg object on the moon is _____.
a. the same
c. less
b. more
d. 6 times the amount
____ 37. The mass of a sheep that weighs 110 N is about _____.
a. 1 kg
c. 110 kg
b. 11 kg
d. 1110 kg
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
____ 38. An object following a straight-line path at constant speed _____.
a. must be falling
b. has a net force acting on it in the direction of motion
c. has zero acceleration
d. none of the above
____ 39. Friction _____.
a. comes from microscopic bumps that act as obstructions to the object’s motion
b. is the name given to the force acting between surfaces sliding past one another
c. acts in a direction that opposes the motion of the object
d. all of the above
____ 40. A 15 N force and a 45 N force act on each other in opposite directions. What is the net force on the object?
a. 15 N
c. 45 N
b. 30 N
d. 60 N
____ 41. A 15 N force and a 45 N force act on an object in the same direction. What is the net force on the object?
a. 15 N
c. 45 N
b. 30 N
d. 60 N
____ 42. Equilibrium occurs when _____.
a. all the forces acting on the object are balanced
b. the net force on the object is zero
c. all of the above
d. none of the above
____ 43. A girl whose weight is 500 N hangs from the middle of a bar supported by two vertical strands of rope. What
is the tension in each rope?
a. 0 N
c. 500 N
b. 250 N
d. 100 N
____ 44. A clothesline is stretched between two trees. A tire hangs in the middle of the line and the two halves of the
line make equal angles with the horizontal. The tension in each half of the line is _____.
a. half the weight of the tire
c. more than half the weight of the tire
b. less than half the weight of the tire
d. none of the above
____ 45. A bag of sports equipment has a mass of 10 kg and a weight of _____.
a. 0.98 N
c. 98 N
b. 9.8 N
d. 980 N
____ 46. The acceleration produced by a net force on an object is _____.
a. directly proportional to the magnitude of the net force
b. in the opposite direction as the net force
c. directly proportional to the mass of the object
d. all of the above
____ 47. If the force acting on a shopping cart quadruples, what happens to the cart’s acceleration?
a. it quadruples
c. it is cut in half
b. it doubles
d. it gets squared
____ 48. A girl whose weight is 400 N hangs from a bar supported by two strands of rope. What is the tension in each
strand?
a. 400 N
c. 200 N
b. 300 N
d. 100 N
____ 49. The unit of pressure is _____.
a. the Newton
c. kilograms
b. meters per second squared
d. Pascals
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
____ 50. Which of the following would exert the least amount of pressure on the ground?
a. A woman standing in running shoes
c. a woman standing in high heels
b. A woman sitting on the ground
d. a woman standing on skis
____ 51. A tennis ball and a solid steel ball of the same size are dropped at the same time. In the absence of air
resistance, which ball has the greater acceleration?
a. the steel ball
b. neither
c. the tennis ball
____ 52. A tennis ball and a solid steel ball of the same size are dropped at the same time. In the absence of air
resistance, which ball has the greater force acting on it?
a. the steel ball
b. neither
c. the tennis ball
____ 53. Taking air resistance into consideration, a skydiver’s velocity _____ and his acceleration decreases.
a. increases
c. remains constant
b. decreases
d. is zero
____ 54. Suppose the force of friction on a sliding object is 25 N. The force needed to maintain a constant velocity is
_____.
a. 0 N
c. less than 25 N
b. 25 N
d. more than 25 N
____ 55. A 20 N object encounters 4 N of air resistance. The magnitude of the net force on the object is _____.
a. 0 N
c. 16 N
b. 24 N
d. 20.4 N
____ 56. A sports car has a mass of 1,500 kg and accelerates at 5 m/s2. What is the magnitude of the force acting on
the sports car?
a. 300 N
c. 2250 N
b. 1500 N
d. 7500 N
____ 57. A tow truck exerts a force of 2000 N on a car, accelerating at 1 m/s2. What is the mass of the car?
a. 667 kg
c. 2000 kg
b. 1000 kg
d. 8000 kg
____ 58. You pull horizontal on a 50 kg crate with a force of 450 N and the friction force on the crate is 250 N. The
acceleration of the crate is _____.
a. 2 m/s2
c. 9 m/s2
b. 4 m/s2
d. 14 m/s2
____ 59. How much force is needed to accelerate a 4 kg physics book at 2 m/s2?
a. 0 N
c. 0.5 N
b. 2.0 N
d. 8.0 N
____ 60. A 6 N falling object encounters 6 N of air resistance. The magnitude of the net force on the object is _____.
a. 0 N
c. 12 N
b. 6 N
d. 8.5 N
____ 61. An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to
this force is the _____.
a. arrow’s push against the bowstring
c. air resistance against the bow
b. weight of the arrow
d. grip of the archers hand on the bow
____ 62. A high school student hits a nail with a hammer. During the collision, there is a force _____.
a. on the nail but not on the hammer
b. on the nail and also on the hammer
c. on the hammer but not on the nail
____ 63. A rocket is able to accelerate in the vacuum of space when it fires its engines. The force that propels the
rocket is the force _____.
a. of the rocket on the exhaust gases
b. of the exhaust gases on the rocket
c. none of the above
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
____ 64. Forces always occur ______.
a. as single quantities
c. in pairs
b. by themselves
d. in triplets
____ 65. According to Newton’s third law, if you push gently on something, it will push _____.
a. gently on something else
c. gently on you
b. on you only if you are not moving
d. all of the above
____ 66. A force is exerted on the tires of a car to accelerate the car along the road. The force is exerted by the _____.
a. road
c. tires
b. engine
d. air
____ 67. A woman weighing 450 N sits on the floor. She exerts a force of _____ on the floor.
a. 4.5 N
c. 450 N
b. 45 N
d. 4500 N
____ 68. Nellie Newton holds an apple in her hand. If action is Earth pulling on the apple, then reaction is _____.
a. her hand providing a normal force on the apple
b. her hand pushing up on the apple
c. both (a) and (b)
d. neither (a) nor (b)
____ 69. As a ball falls, the action force is the pull of Earth’s mass on the ball. What is the reaction to this force?
a. The pull of the ball’s mass on Earth.
c. Nonexistent in this case.
b. The acceleration of the ball.
d. Air resistance acting on the ball.
____ 70. A person is attracted towards the center of Earth by a 440 N gravitational force. The force with which Earth
is attracted toward the person is _____.
a. less than 440 N
c. more than 440 N
b. 440 N
d. the weight of Earth
____ 71. An unfortunate bug splatters against the windshield of a moving car. Compared to the deceleration of the car,
the deceleration of the bug is _____.
a. larger
b. the same
c. smaller
____ 72. Your friend says that the heavyweight champion of the world cannot exert a force of 95 N on piece of tissue
paper with his best punch. The tissue paper is held in midair; no wall and no tricks.
a. You agree that it cannot be done.
b. You disagree because a good punch easily delivers this much force.
c. You have reservations about this claim
____ 73. Earth pulls on the moon and similarly, the moon pulls on Earth. This is evidence that the _____
a. Earth and moon are simply pulling in each other
b. Earth and moon’s pull comprise an action-reaction pair
c. both (a) and (b)
d. neither (a) nor (b)
____ 74. A karate chop delivers a blow of 2300 N to a board that breaks. The force that acts on the hand during this
feat is _____.
a. less than 2300 N
c. 2300 N
b. more than 2300 N
d. cannot be determined
____ 75. A woman weighing 520 N stands on the floor. The floor exerts a force of _____ on the woman.
a. 5.2 N
c. 520 N
b. 52 N
d. 5200 N
____ 76. A large truck and a small car traveling at the same speed have a head-on collision. Which vehicle will
undergo the greater change in velocity?
a. the small car
b. neither
c. the large truck
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
____ 77. An unfortunate bug splatters against the windshield of a moving car. Compared to the force of the car on the
bug, the force of the bug on the car is _____.
a. larger
b. the same
c. smaller
____ 78. Whenever an object exerts a force on another object, the second object exerts a force of the same magnitude,
but in the opposite direction to that of the first object.
a. Sometimes true.
b. Always true.
c. Always false.
____ 79. A player hits a ball with a bat. The action force is the impact of the bat against the ball. What is the reaction
to this force?
a. The force of the ball against the bat.
b. The weight of the ball.
c. Air resistance on the ball.
d. The grip of the player’s hand against the bat.
____ 80. A player catches a ball. Consider the action force to be the impact of the ball against the player’s glove.
What is the reaction to this force?
a. The force the glove exerts on the ball.
b. Friction of the ground against the player’s shoes.
c. The player’s grip on the glove.
d. none of the above
____ 81. If a horse pulls on a wagon at rest, the wagon pulls back equally on the horse. Can the wagon be set into
motion?
a. Yes, because there is a net force acting on the wagon.
b. Yes, because there is a time delay between action and reaction.
c. No, because the forces cancel each other.
d. none of the above
____ 82. Bronco the skydiver falls toward Earth. The attraction of Earth on Bronco pulls him down. The reaction to
this force is _____.
a. Bronco pushing against the Earth’s surface
b. Bronco pulling up on Earth
c. Earth’s surface pushing against Bronco
d. none of the above
____ 83. Which of the following is most closely related to mass?
a. inertia in motion
c. momentum
b. inertia
d. change in momentum
____ 84. Which of the following is most closely related to momentum?
a. inertia in motion
c. impulse
b. inertia
d. mass time acceleration
____ 85. Which has the most momentum?
a. 10 kg at 5 m/s
c. 100 kg at rest
b. 20 kg at 2 m/s
d. 5 kg at 50 m/s
____ 86. Which has the most mass?
a. 10 kg at 5 m/s
c. 100 kg at rest
b. 20 kg at 2 m/s
d. 5 kg at 50 m/s
____ 87. When the force of impact is extended over a longer period of time, _____.
a. the impulse decreases
c. the momentum increases
b. the impulse increases
d. the collision is inelastic
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
____ 88. Impulse _____.
a. is the change in momentum
c. is measured in Newton-seconds
b. equals force multiplied by time
d. all of the above
____ 89. Given a constant force, tripling the duration of impact will also _____.
a. triple the force
c. triple the mass
b. triple the impulse
d. reduce the velocity by to two-thirds
____ 90. Given a constant impulse, tripling the duration of impact will also _____.
a. triple the force
c. triple the mass
b. triple the impulse
d. reduce the force by to two-thirds
____ 91. You experience an impulse every time you _____.
a. catch a ball
c. catch, then throw a ball
b. throw a ball
d. all of the above
____ 92. Which of the following situations most closely resembles an inelastic collision?
a. a tennis racquet striking a tennis ball
c. a player kicking a soccer ball
b. a baseball being struck by a bat
d. a linebacker tackling a running back
Numeric Response
Write down the appropriate equation for each problem. Replace the variables by substituting numeric values from the
problem into your equation. Solve the problem for the unknown variable. Make sure your response includes a numerical
answer followed by a unit.
1. A cyclist travels 15 km in 30 minutes. What is the average speed of the biker?
2. A skateboarder starting from rest accelerates down a ramp at 2 m/s2 for 2 s. Calculate the speed of the skater.
3. A student standing on a balcony drops a water balloon on his friend as practical joke. If the balloon takes 1.75 s
to hit its target, how high is the balcony that the balloon was dropped from? (Ignore the both air resistance
and the height of the victim.)
4. A motorboat is driven across a river at 3.0 km/h at a right angle to the current, which is flowing at 10 km/h.
Sketch a diagram of this problem labeling each vector, then calculate the resultant vector.
5. An airplane heads north at a speed of 230 km/h with a crosswind blowing from the west at 80 km/h. Sketch a
diagram of this problem labeling each vector, then calculate the resultant vector.
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
6. How much does a 10 kg bag of dog food weigh? State your answer in Newtons.
7. A person weighs 650 N. What is the mass of the person?
8. Two forces of 10 N both act on an object. The angle between the forces is a right angle. What is the magnitude
of resultant?
9. You push with 35 N of force on a 5 kg box across a frictionless surface. What is the block’s acceleration?
10. You push with 150 N of force on a 25 kg box across a frictionless surface. What is the block’s acceleration?
11. A water balloon dropped from a balcony speeds up from 0 m/s to 29.4 m/s during the first 3 s of free fall.
What is the acceleration of the water balloon?
12. A force of 1000 N is exerted over an area of 250 m2. Calculate the pressure exerted on this space.
13. A force of 350 N is exerted over an area of 15 m2. Calculate the pressure exerted on this space.
14. Two blocks of different masses experience the same force. The smaller block has one-third the mass of the
larger block. How many times faster does the smaller block accelerate?
15. If you push off the ground with a force of 425 N when you jump upward, what force pushes Earth downward?
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
16. The maximum thrust force that can be created using a toy rocket kit is 49 N. Calculate the maximum mass
possible for a successful launch.
17. If you stomp on the ground with a force of 175 N downward, with what force does Earth push upward?
18. Two blocks of different masses experience the same force. The larger block has quadruple the mass of the
smaller block. How many times faster does the smaller block accelerate?
19. What thrust force is required to successfully launch a 45 kg rocket?
20. A bowling ball has a mass of 7 kg and a velocity of 3 m/s.
a.
What is the ball’s momentum?
b.
Calculate the force needed to stop the ball in 1.0 s.
21. An 80 kg hockey player skates at 6 m/s.
a.
Calculate the momentum of the hockey player.
b.
If the hockey player experiences an inelastic collision with another player of the same mass, how
fast does the pair move off together?
22. A cue ball with a mass of 0.25 kg rolling at 1.0 m/s collides with the 8-ball and stops. If the mass of the 8ball is 0.2 kg, how fast does it move away from the cue ball?
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
23. Suppose you want to lift a 60 kg block.
a.
How much work is required to raise it to a height of 20 m?
b.
How much power is used if you lift it in 15 s?
24. A 5 kg ball sits at the top of a ramp that is 3 m high. How much potential energy does the ball have?
25. A 1000 kg truck moves at 22 m/s. How much kinetic energy does the truck have?
26. If a car jack is able to lift a 3500 N car with an input force just 50 N, what is the mechanical advantage of the
jack?
27. If a light bulb uses 60 W of power for every 120 W put into it, what is the efficiency of the light bulb?
Short Answer
Respond to each of the following items using complete sentences and appropriate grammar. Be sure to address all parts
of each problem. Use additional paper if necessary.
1. An airplane flies at 295 km/h parallel to the direction of the wind. The wind speed is 40 km/h. What are the
two possible speeds of the plane relative to the ground? Explain your answer.
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Name: ________________________________________ Block: _____ Date: _____/_____/_____
Conceptual Physics
2. Write a brief paragraph summarizing the early theories of motion of the following scientists: Copernicus,
Aristotle, and Galileo. List the scientists in chronological order of there contribution beginning with the
earliest in your summary.
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3. Describe the difference between momentum and impulse in terms of mathematical products. What
relationship exists between these two quantities?
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4. Explain why an impulse is greater when bouncing occurs.
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5. What is the difference between an elastic and an inelastic collision? Give an example of each.
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