Conceptual Physics Semester Exam 1
Multiple Choice
Identify the choice that best completes the statement or answers the question.
1. A vector is a quantity that has
a. magnitude and time.
b. time and direction.
c. magnitude and direction.
2. A scalar is a quantity that has
a. direction.
b. magnitude.
c. time.
d. color.
3. When representing velocity as a vector ,
a. the direction of the arrow shows the direction of motion.
b. the length of the arrow represents the speed.
c. the length of the arrow is drawn to a suitable scale.
d. all of the above
e. none of the above
4. Which of the following would NOT be considered a projectile?
a. A cannonball thrown straight up
b. A cannonball rolling down a slope
c. A cannonball rolling off the edge of a table
d. A cannonball thrown through the air
e. All of the above are projectiles.
5. The horizontal component of a projectile's velocity is independent of
a. the range of the projectile.
b. time.
c. the vertical component of its velocity.
6. In the absence of air friction, the vertical component of a projectile's velocity doesn't
change as the projectile moves.
a. Always false
b. Always true
c. Sometimes true
7. At the instant a ball is thrown horizontally with a large force, an identical ball is dropped
from the same height. Which ball hits the ground first?
a. Neither. They both hit the ground at the same time.
b. The dropped ball
c. The horizontally thrown ball
8. In the absence of air resistance, the angle at which a thrown ball will go the farthest is
a. 15 degrees .
b. 30 degrees .
c. 45 degrees .
d. 60 degrees.
e. 75 degrees.
9. A ball thrown in the air will never go as far as physics ideally would predict because
a. one can never throw the ball fast enough.
b. gravity is acting.
c. air friction slows the ball.
d. ideally the ball would never land.
e. all of the above
10. At what part of a path does a projectile have minimum speed?
a. When it returns to the ground
b. Halfway to the top
c. At the top of its path
d. When it is thrown
e. There's not enough information to say.
11. A projectile launched horizontally hits the ground in 0.8 seconds. If it had been launched
with a much higher speed in the same direction, it would have hit the ground (neglecting
Earth's curvature and air resistance) in
a. more than 0.8 s.
b. 0.8 s.
c. less than 0.8 s.
12. A baseball is hurled into the air at an angle of 30 degrees above the horizontal and lands on
a target that is at the same level as that where the baseball started. The baseball will also
land on the target if it is thrown at an angle of
a. 20 degrees.
b. 40 degrees.
c. 50 degrees.
d. 60 degrees.
e. none of the above
13. A cannonball is launched horizontally from a tower. If the cannon has a barrel velocity of
60 m/s, where will the cannonball be 1 second later? (Neglect air resistance.)
a. 6 m downrange
b. 30 m downrange
c. 60 m downrange
d. 300 m downrange
e. none of the above
14. Jose can jump vertically 1 meter from his skateboard when it is at rest. When the
skateboard is moving horizontally, Jose can jump
a. no higher.
b. higher.
15. Suppose a small plane can fly at 170 km/h relative to the surrounding air. Suppose also that
there is a 60 km/h tailwind. How fast does the plane's shadow move across the ground?
a. 5 km/h
b. 60 km/h
c. 110 km/h
d. 170 km/h
e. 230 km/h
16. At the instant a ball is thrown horizontally with a large force, an identical ball is dropped
from the same height. Which ball hits the ground first?
a. Neither—they both hit the ground at the same time.
b. The horizontally thrown ball
c. The dropped ball
17. A ball is thrown straight upward at 10 m/s. Ideally (no air resistance), the ball will return to
the thrower's hand with a speed of
a. 0 m/s.
b. 5 m/s.
c. 10 m/s.
d. 20 m/s.
e. There is not enough information to say.
18. Speed is
a. a measure of how fast something is moving.
b. always measured in terms of a unit of distance divided by a unit of time.
c. the distance covered per unit time.
d. all of the above.
e. none of the above.
19. One possible unit of speed is
a. miles per hour.
b. light years per century.
c. kilometers per hour.
d. all of the above.
e. none of the above.
20. When you look at the speedometer in a moving car, you can see the car's
a. average distance traveled.
b. instantaneous acceleration.
c. average speed.
d. instantaneous speed.
e. average acceleration.
21. Acceleration is defined as the CHANGE in
a. time it takes to move from one place to another place.
b. velocity of an object.
c. distance divided by the time interval.
d. velocity divided by the time interval.
e. time it takes to move from one speed to another speed.
22. Suppose you are in a car that is going around a curve. The speedometer reads a constant 30
miles per hour. Which of the following is NOT true?
a. You and the car are accelerating.
b. Your acceleration is constantly changing.
c. Your velocity is constant.
d. Your direction is constantly changing.
e. Your speed is constant.
23. A train travels 6 meters in the first second of travel, 6 meters again during the second
second of travel, and 6 meters again during the third second. Its acceleration is
a. 0 m/s2.
b. 6 m/s2.
c. 12 m/s2.
d. 18 m/s2.
e. none of the above
24. 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
b. 1.67 m/s2
c. 6 m/s2
d. 7 m/s2
e. none of the above
25. As an object falls freely in a vacuum, its
a. velocity increases.
b. acceleration increases.
c. both A and B.
d. none of the above.
26. In the absence of air resistance, objects fall at constant
a. speed.
b. velocity.
c. acceleration.
d. distances each successive second.
e. all of the above
27. Suppose an object is in free fall. Each second the object falls
a.
b.
c.
d.
e.
the same distance as in the second before.
a larger distance than in the second before.
with the same instantaneous speed.
with the same average speed.
none of the above
28. If you drop a feather and a coin at the same time in a tube filled with air, which will reach
the bottom of the tube first?
a. The feather
b. Neither—they will both reach the bottom at the same time.
c. The coin
29. Suppose you take a trip that covers 180 km and takes 3 hours to make. Your average speed
is
a. 30 km/h.
b. 60 km/h.
c. 180 km/h.
d. 360 km/h.
e. 540 km/h.
30. A ball is thrown straight up. At the top of its path its instantaneous speed is
a. 0 m/s.
b. about 5 m/s.
c. about 10 m/s.
d. about 20 m/s.
e. about 50 m/s.
31. A ball is thrown straight up. At the top of its path its acceleration is
a. 0 m/s2.
b. about 5 m/s2.
c. about 10 m/s2.
d. about 20 m/s2.
e. about 50 m/s2.
32. When something 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
Earth's surface?
a. 0 m/s2
b. about 5 m/s2
c. about 10 m/s2
d. about 20 m/s2
e. about 50 m/s2
33. A freely falling object starts from rest. After falling for 6 seconds, it will have a speed of
about
a. 6 m/s.
b.
c.
d.
e.
30 m/s.
60 m/s.
300 m/s.
more than 300 m/s.
34. If you drop a feather and a coin at the same time in a vacuum tube, which will reach the
bottom of the tube first?
a. Neither-they will both reach the bottom at the same time.
b. The coin
c. The feather
35. A pencil lies on your desk. If the Earth is moving around the sun at a speed of 30 km/s,
how fast is the pencil moving relative to the desk? How fast is the pencil moving relative
to the sun?
a. 0 km/s; 0 km/s
b. 0 km/s; 30 km/s
c. 30 km/s; 30 km/s
d. There is not enough information to answer these questions.
36. Acceleration is defined as
a. the rate at which distance is covered
b. the rate at which an object freely falls from rest
c. the rate at which velocity itself changes
d. the distance an object has fallen
37. The momentum of an object is defined as the object's
a. mass times its velocity.
b. force times the time interval.
c. force times its acceleration.
d. mass times it acceleration.
e. velocity times the time interval.
38. Compared to a sports car moving at 30 miles per hour, the same sports car moving at
miles per hour has
a. twice as much momentum.
b. four times as much momentum.
c. the same momentum.
39. If the momentum of an object changes and its mass remains constant,
a. it is accelerating (or decelerating).
b. there is a force acting on it.
c. its velocity is changing.
d. all of the above
e. none of the above
40. The reason padded dashboards are used in cars is that they
a.
b.
c.
d.
e.
look nice and feel good.
decrease the impulse in a collision.
increase the force of impact in a collision.
decrease the momentum of a collision.
increase the time of impact in a collision.
41. A table tennis ball launcher is fired. Compared to the force on the ball, the force on the
launcher is
a. larger.
b. the same.
c. smaller.
42. Momentum of a system is conserved only when
a. there are no internal forces acting on the system.
b. the system is not moving.
c. there are no forces acting on the system.
d. there is no net external force acting on the system.
e. the system has zero momentum.
43. A collision is considered elastic if
a. there is no lasting deformation.
b. the objects don’t stick together.
c. the objects that collide don't get warmer.
d. after the collision, the objects have the same shape as before the collision.
e. all of the above
44. Which of the following has the largest momentum?
a. A large truck parked in a parking lot
b. A tightrope walker crossing Niagara Falls
c. The science building at your school
d. A pickup truck traveling down the highway
e. A dog running down the street
45. A freight train rolls along a track with considerable momentum. If it were to roll at the
same speed but had twice as much mass, its momentum would be
a. zero.
b. unchanged.
c. quadrupled.
d. doubled.
46. In order to catch a ball, a baseball player moves his or her hand backward in the direction
of the ball's motion. Doing this reduces the force of impact on the player's hand principally
because
a. the time of impact is decreased.
b. the time of impact is increased.
c. the velocity of the hand is reduced.
d. the momentum of impact is reduced.
e. none of the above
47. The force of an apple hitting the ground depends upon
a. the speed of the apple just before it hits.
b. the time of impact with the ground.
c. whether or not the apple bounces.
d. air resistance on the apple as it falls.
e. all of the above
48. When you jump off a step, you usually bend your knees as you reach the ground. By doing
this, the time of the impact is about 10 times more what it would be in a stiff-legged
landing, and the average force on your body is reduced by
a. less than 10 times.
b. about 10 times.
c. more than 10 times.
49. Two gliders having the same mass and speed move toward each other on an air track and
stick together. After the collision, the velocity of the gliders is
a. twice the original velocity.
b. one half the original velocity.
c. zero.
d. the same as the original velocity.
e. There is not enough information to say.
50. The force that accelerates a rocket into outer space is exerted on the rocket by
a. the exhaust gases.
b. Earth's gravity.
c. atmospheric pressure.
d. rocket's wings.
e. none of the above
51. Superman is at rest in space when he throws an asteroid that has more mass than he does.
Which moves faster, Superman or the asteroid?
a. Superman
b. The asteroid
c. They both move at the same speed.
52. A 2-kg ball is thrown at 3 m/s. What is the ball's momentum?
a. 2 kg·m/s
b. 3 kg·m/s
c. 6 kg·m/s
d. 9 kg·m/s
e. none of the above
53. A 4.0-kg ball has a momentum of 20.0 kg·m/s. What is the ball's speed?
a.
b.
c.
d.
e.
0.2 m/s
5.0 m/s
20.0 m/s
80.0 m/s
none of the above
54. A ball is moving at 6.0 m/s and has a momentum of 24.0 kg·m/s. What is the ball's mass?
a. 0.3 kg
b. 4.0 kg
c. 24.0 kg
d. 144.0 kg
e. none of the above
55. The astronomer Copernicus publicly stated in the 1500s that Earth
a. does not move.
b. revolves around the sun.
c. is slowing down.
d. moves in a straight line.
e. is the center of the solar system.
56. Friction is a force that always acts
a. perpendicular to an object's motion.
b. opposite to an object's motion.
c. in the same direction as an object's motion.
57. 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. that is not moving will never move unless a force acts on it.
d. at rest will remain at rest unless acted on by an outside force.
e. will do all of the above.
58. The law of inertia applies to
a. objects at rest.
b. moving objects.
c. both moving and nonmoving objects.
59. An object following a straight-line path at constant speed
a. has no forces acting on it.
b. has a net force acting on it in the direction of motion.
c. has zero acceleration.
d. must be moving in a vacuum.
e. none of the above
60. Friction
a. comes from microscopic bumps that act as obstructions to the object's motion.
b.
c.
d.
e.
is the name given to the force acting between surfaces sliding past one another.
acts in a direction that opposes the motion of an object.
all of the above
none of the above
61. Compared to its weight on Earth, a 10-kg object on the moon will weigh
a. the same amount.
b. less.
c. more.
62. Compared to its mass on Earth, the mass of a 10-kg object on the moon is
a. the same.
b. more.
c. less.
63. The mass of a lamb that weighs 110 N is about
a. 1 kg.
b. 11 kg.
c. 110 kg.
d. 1100 kg.
e. none of the above
64. Which has more mass, a kilogram of feathers or a kilogram of iron?
a. The feathers
b. The iron
c. Neither—they both have the same mass.
65. How much does a 3.0-kg bag of bolts weigh?
a. 7.2 N
b. 14.4 N
c. 22.8 N
d. 29.4 N
e. 58.8 N
66. Accelerations are produced by
a. forces.
b. velocities.
c. accelerations.
d. masses.
e. none of the above
67. How does acceleration of an object change in relation to its mass? It is
a. directly proportional.
b. Acceleration doesn't depend on mass at all.
c. inversely proportional.
68. When an object reaches terminal velocity its acceleration is
a. 0 m/s2.
b. 4.9 m/s2.
c. 9.8 m/s2.
69. When a woman stands with two feet on a scale, the scale reads 280 N. When she lifts one
foot, the scale reads
a. less than 280 N.
b. more than 280 N.
c. 280 N.
70. Suppose the force of friction on a sliding object is 25 N. The force needed to maintain a
constant velocity is
a. more than 25 N.
b. 25 N
c. less than 25 N.
71. A book weighs 4 N. When held at rest in your hands, the net force on the book is
a. 0 N.
b. 0.4 N.
c. 4 N.
d. 39 N.
e. none of the above
72. An object has a constant mass. A constant force on the object produces constant
a. velocity.
b. acceleration.
c. both A and B
d. none of the above
73. A force of 3 N accelerates a mass of 3 kg at the rate of 1 m/s2. The acceleration of a mass
of 6 kg acted upon by a force of 6 N is
a. twice as much.
b. half as much.
c. the same.
d. none of the above
74. A box is dragged without acceleration in a straight-line path across a level surface by a
force of 13 N. What is the frictional force between the box and the surface?
a. 13 N
b. Less than 13 N
c. More than 13 N
d. Need more information to say.
75. Pressure is defined as
a. time per area.
b.
c.
d.
e.
velocity per time.
force per time.
force per area.
distance per time.
76. The unit of pressure is
a. newtons per meter.
b. newtons per square meter (or pascals).
c. the newton.
d. the meter.
e. meters per second squared.
77. Which of the following would exert the most pressure on the ground?
a. A woman standing in running shoes
b. A woman standing on skis
c. A woman standing in high-heel shoes
78. A tennis ball and a solid steel ball with the same diameter are dropped at the same time.
Which ball has the greater force acting on it?
a. The steel ball
b. The tennis ball
c. They both have the same force acting on them.
79. A block is at rest on an incline. The force of friction necessary to prevent the block from
sliding increases when the incline angle is
a. increased.
b. decreased.
c. neither A nor B (Force of friction stays the same.)
80. If the force acting on a cart doubles, what happens to the cart's acceleration?
a. It quarters.
b. It halves.
c. It stays the same.
d. It doubles.
e. It quadruples.
81. Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that
the cart's mass doubles, what happens to the cart's acceleration?
a. It quarters.
b. It halves.
c. It stays the same.
d. It doubles.
e. It quadruples.
82. You are on a frozen pond, and the ice starts to crack. If you lie down on the ice and begin
to crawl, this will
a.
b.
c.
d.
increase the pressure on the ice.
decrease the pressure on the ice.
increase the total force on the ice.
decrease the total force on the ice.
83. A 20-N falling object encounters 4 N of air resistance. The magnitude of the net force on
the object is
a. 0 N.
b. 4 N.
c. 16 N.
d. 20 N.
e. none of the above
84. A sportscar has a mass of 1500 kg and accelerates at 5 meters per second squared. What is
the magnitude of the force acting on the sportscar?
a. 300 N.
b. 1500 N.
c. 2250 N.
d. 7500 N.
e. none of the above
85. A tow truck exerts a force of 2000 N on a car, accelerating it at 1 m/s/s. What is the mass
of the car?
a. 667 kg
b. 1000 kg
c. 2000 kg
d. 8000 kg
e. none of the above
86. A jet has a mass of 40,000 kg. The thrust for each of four engines is 20,000 N. What is the
jet's acceleration when taking off?
a. 0.3 m/s2
b. 0.5 m/s2
c. 1 m/s2
d. 2 m/s2
e. none of the above
87. A jumbo jet cruises at a constant velocity when the total thrust of the engines on the jet is
50,000 N. How much air resistance acts on the jet?
a. 0 N
b. 25,000 N
c. 50,000 N
d. 75,000 N
e. 100,000 N
True/False
Indicate whether the statement is true or false.
88. The rate at which distance is covered is called speed.
89. Average speed is defined as the time it takes for a trip divided by the distance.
90. A unit of velocity is the meter.
91. The rate at which velocity changes with time is called acceleration.
92. A unit of acceleration is meters per second.
93. As a ball falls freely, the distance it falls each second is the same.
94. Momentum is defined as an object's mass times its velocity.
95. Impulse is defined as the force exerted on an object times the time it lasts.
96. When two objects collide and completely bounce apart with no lasting deformation or
generation of heat, the collision is said to be elastic.
97. When two objects collide and stick together, the collision is said to be inelastic.
98. Perfectly elastic collisions between large objects are uncommon in the everyday world.
99. Automobile dashboards that are padded lengthen the time of impact in case of a collision.
100. A force can be simply defined as a push or a pull.