Deck 2: Motion

Question 1

The rate at which an object's velocity changes with time is called its

A) instantaneous velocity.
B) motion.
C) speed.
D) acceleration.

Answer 1

D

Question 2

An object that is moving in a linear path with an acceleration in the direction opposite to the motion has a(n) ______________ velocity.

A) constant
B) increasing
C) decreasing
D) none of these

Answer 2

C

Question 3

A speedometer indicates ______________ if the automobile is traveling forward.

A) instantaneous acceleration
B) instantaneous speed
C) instantaneous velocity
D) average speed
E) average acceleration

Answer 3

B

Question 4

Velocity is similar to speed, but a ________ is also involved in velocity.

A) acceleration
B) direction
C) position
D) scalar

Question 5

Which one of the following is not an area of physics?

A) Mechanics
B) Optics
C) Algebra
D) Acoustics

Question 6

An automobile's acceleration cannot be changed by using the

A) gas pedal.
B) brake pedal.
C) steering wheel.
D) stick shift.
E) turn signal.

Question 7

An automobile's acceleration may be changed by using the

A) windshield wipers.
B) steering wheel.
C) radio.
D) horn.

Question 8

Displacement divided by time gives

A) average acceleration.
B) average velocity.
C) average speed.
D) average distance.

Question 9

Average speed multiplied by time gives

A) average acceleration.
B) displacement.
C) instantaneous speed.
D) distance.

Question 10

The magnitude of a displacement is ______________ the magnitude of the distance traveled.

A) always unequal to
B) less than or equal to
C) always equal to
D) greater than or equal to
E) none of these; the two cannot be compared.

Question 11

Motion necessarily involves

A) a change in velocity.
B) a change in speed.
C) a change in direction.
D) a change in position.
E) all of these

Question 12

If an object moves with constant velocity,

A) its speed is constant.
B) its direction is constant.
C) its average speed is constant.
D) its distance traveled per unit time is constant.
E) all of these

Question 13

The straight-line distance and direction between two points are, together, called

A) velocity.
B) displacement.
C) distance.
D) acceleration.

Question 14

The magnitudes of two horizontal displacements are 4 m and 9 m, respectively. Given that the vectors may be in either the plus or the minus direction, they cannot be added together to give a total displacement of

A) -13 m.
B) -5 m.
C) 5 m.
D) 13 m.
E) 4 m.

Question 15

Distance covered per unit of time is called

A) speed.
B) acceleration.
C) velocity.
D) displacement.

Question 16

For which of the following is the acceleration constant?

A) Nonuniform speed
B) Free fall
C) Uniform circular motion
D) None of these

Question 17

If the instantaneous velocity of an object is constant, then so is its

A) velocity.
B) distance.
C) acceleration.
D) displacement.

Question 18

An acceleration may result from

A) a change in speed.
B) a change in direction.
C) a change in both speed and direction.
D) all of these

Question 19

The distance traveled by an automobile moving at a constant velocity is

A) directly proportional to the time.
B) directly proportional to the time squared.
C) inversely proportional to the time squared.
D) inversely proportional to the time.
E) none of these

Question 20

Which one of the following is true for deceleration?

A) The acceleration is in the direction opposite the motion.
B) The acceleration is zero.
C) The acceleration is necessarily negative.
D) The velocity remains constant.

Question 21

Centripetal means

A) center seeking
B) pulls outward
C) constant
D) fast
E) none of these

Question 22

A freely falling object has a constant acceleration of 9.8 m/s². This means that

A) the object's displacement changes by 9.8 m every second squared.
B) the object's speed increases by 9.8 m/s each second.
C) the object's acceleration increases by 9.8 m/s² each second.
D) the object travels 9.8 m each second.

Question 23

In the equation a_c= v²/r for centripetal acceleration, the v stands for

A) volume.
B) very.
C) speed.
D) velociraptor.

Question 24

All the following may be represented by vectors except

A) velocity.
B) acceleration.
C) speed.
D) displacement.

Question 25

An object in uniform circular motion has

A) constant acceleration.
B) variable radial distances.
C) constant velocity.
D) constant speed.

Question 26

Which of the following is a possible unit of acceleration?

A) m/s²
B) m × s
C) m²/s
D) m/s

Question 27

As a block slides down a 33° frictionless incline, its acceleration

A) decreases with distance.
B) remains constant.
C) is greatest at the bottom of the incline.
D) is greatest at the top of the incline.

Question 28

Which of the following statements is not true?

A) Displacement has a direction and a magnitude.
B) Acceleration has a magnitude only.
C) Speed has a magnitude only.
D) Velocity has a magnitude and a direction.

Question 29

An object that is moving in a linear path with an acceleration at a right angle to the motion has a(n) ______________ velocity.

A) changing
B) increasing
C) decreasing
D) constant

Question 30

In the equation a_c= v²/r for centripetal acceleration, the r stands for

A) diameter.
B) distance.
C) radius.
D) rate.

Question 31

An object travels in a circle of radius 2.0 m with a constant speed of 4.0 m/s. What is the direction of its acceleration?

A) Toward the center of the circle
B) Normal to the plane of the circle
C) Insufficient data given for determination
D) Tangential to the circle
E) None of these

Question 32

The distance traveled by a dropped object in free fall is directly proportional to

A) the time squared.
B) its weight.
C) its mass.
D) none of these.

Question 33

If the magnitude of the velocity of an object increases, we may be sure that during the time of this increase,

A) the object is accelerated.
B) the acceleration of the object increases.
C) the object is moving in a straight path.
D) the object is changing direction.
E) none of these

Question 34

An object with a mass of 5 kg is dropped and takes 9 s to hit the ground. Then another object with a mass of 10 kg is dropped from the same point. How long does it take to hit the ground?

A) 9 s
B) 18 s
C) 5 s
D) 81 s
E) 729 s

Question 35

A freely falling object

A) has a uniformly increasing velocity.
B) is unaffected by gravity.
C) has a uniformly increasing acceleration.
D) has a uniformly increasing displacement.

Question 36

A car is moving down a freeway in a straight line at a constant rate of 32.0 m/s for 3.0 s. Its acceleration is

A) 9.8 m/s².
B) 9.8 m/s.
C) zero.
D) 32.0 m/s.
E) 11.0 m/s².

Question 37

An object that is moving with an acceleration different from zero will always have a(n) ______________ velocity.

A) changing
B) increasing
C) constant
D) decreasing

Question 38

An object that is moving in a linear path with an acceleration in the direction of motion has a(n) ______________ velocity.

A) constant
B) increasing
C) decreasing
D) none of these

Question 39

An object in free fall has

A) a constant speed.
B) a constant velocity.
C) a velocity that changes 9.8 m/s each second.
D) an acceleration that depends on its mass.

Question 40

An object is dropped from a vertical distance of 25.5 m above the ground, and it takes 2.28 sec to fall that distance. A second identical object to launched from the same height, with a horizontal velocity of 45.9 m/s. How long does the second object take to fall the 25.5 m?

A) More than 2.28 sec
B) Almost 2.28 sec.
C) Less than 2.28 sec
D) Exactly 2.28 sec
E) Much less than 2.28 sec

Question 41

A compass registers ______________.

Question 42

For there to be an acceleration, there must necessarily be a change in ______________.

Question 43

In free fall, the ______________ is constant.

Question 44

If the speed of an object in circular motion is increased by a factor of 3, its centripetal acceleration for the same radius will be multiplied by a factor of

A) 0.111.
B) 0.333.
C) 1.73.
D) 9.
E) 3.

Question 45

A continuous change in position is called ______________.

Question 46

If an object has a constant velocity, then its acceleration is ______________.

Question 47

Distance is a(n) ______________ quantity.

Question 48

A projectile's vertical velocity component

A) changes most rapidly near the top of its trajectory.
B) changes at a constant rate.
C) changes most rapidly near the bottom of its trajectory.
D) does not change.

Question 49

In projectile motion, which of the following is not constant?

A) Vertical velocity
B) Horizontal velocity
C) Acceleration
D) None of these

Question 50

A golfer hits a ball on a level fairway at an angle of 60° relative to the horizontal, and it lands on the green. Another golfer hits a ball with the same speed but at another angle, and it lands on the green by the other ball. What was the launch angle for the second golfer?

A) 30°
B) 20°
C) 45°
D) 40°
E) 10°

Question 51

The direction of the acceleration of an object moving in a circle at constant speed is

A) changing, but pointing in a predictable direction.
B) constant and pointing in only one direction.
C) constant and pointing in two directions.
D) none of these

Question 52

The magnitude of the acceleration of an object moving in a circle at constant speed is

A) inversely proportional to the speed squared.
B) inversely proportional to the speed.
C) inversely proportional to the radius of the circle squared.
D) inversely proportional to the radius of the circle.

Question 53

When running and jumping to score, a basketball player seems to "hang" in the air because

A) his or her acceleration is zero.
B) his or her horizontal velocity is quite small.
C) both components of motion are zero.
D) his or her vertical velocity is quite small.
E) levitation is possible with practice.

Question 54

A golfer hits a ball on a level fairway at an angle of 30° relative to the horizontal, and it lands on the green. Another golfer hits a ball with the same speed but at an angle of 60°, and it lands on the green by the other ball. Which statement is accurate for this situation?

A) One ball is in the air longer than the other.
B) One ball experiences a greater acceleration while in free flight.
C) One ball experiences a smaller acceleration while in free flight.
D) Two balls hit at the same speed but different angles will always land in the same location.
E) Two balls hit at the same speed but different angles can never land in the same location.

Question 55

A speedometer registers ______________.

Question 56

The magnitude of the acceleration of an object moving in a circle at constant speed is

A) variable.
B) directly proportional to the speed squared.
C) directly proportional to the speed.
D) directly proportional to the radius of the circle squared.

Question 57

Physics deals with matter, motion, force, and ______________.

Question 58

The straight-line distance and direction between two points are, together, called ______________.

Question 59

A projectile's horizontal velocity component (ignoring air resistance)

A) does not change.
B) changes most rapidly near the bottom of its trajectory.
C) changes at a variable rate.
D) changes at a constant rate.

Question 60

Speed is a(n) ______________ quantity.

Question 61

Temperature is an example of a(n) ______________ quantity.

Question 62

Physics deals with force, energy, motion, and ______________.

Question 63

A rifle bullet shot horizontally has a vertical acceleration of ______________.

Question 64

In straight-line motion, if a moving object speeds up, the direction of the acceleration is ______________ the direction of the velocity.

Question 65

A(n) ______________ quantity has only magnitude.

Question 66

What two quantities are constant in uniform circular motion? ______________ and ______________

Question 67

For an object in uniform circular motion, the acceleration points toward ______________.

Question 68

On Earth, the magnitude of the velocity of a vertical projectile at its maximum height is equal to ______________.

Question 69

A(n) ______________ quantity has both magnitude and direction.

Question 70

An object moving in a circle with a constant speed has a(n) ______________ directed toward the center of the circle.

Question 71

______________ acceleration is necessary for uniform circular motion.

Question 72

Dropped objects on the Moon fall at a slower rate than on Earth because of a smaller ______________.

Question 73

The SI unit of centripetal acceleration is ______________.
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Question 74

In straight-line motion, if a moving object slows down, the direction of the acceleration is ______________ the direction of the velocity.

Question 75

Two objects are in uniform circular motion at the same speed but at different radii. The one with the ______________ radius has the largest centripetal acceleration.

Question 76

A rifle bullet shot horizontally at a velocity of 9.8 m/s has a horizontal acceleration of ______________.

Question 77

Free-fall motion neglects ______________.

Question 78

The centripetal acceleration of an automobile in uniform circular motion on a flat circular track is supplied by ______________.

Question 79

On Earth, the magnitude of the acceleration of a vertical projectile at its maximum height is equal to ______________.

Question 80

The distance a dropped object travels is proportional to the ______________ of the time.