FINAL EXAM

Question 1

What is Newton’s 1st Law of motion?

Answer 1

A body at rest remains at rest and a body in motion continues to move at constant velocity along a straight line unless acted upon by an external force.

Question 2

What is Newton’s 2nd Law of motion?

Answer 2

Question 3

What is Newton’s 3rd Law of motion?

Answer 3

For every action force on an object there is a reaction force that is equal in magnitude and opposite in direction. Third Law Force Pairs

Question 4

When the man pushes a refrigerator across a kitchen floor at a constant speed, the force of friction between the refrigerator and the floor is

A. equal and in the opposite direction as the man’s push.

B. equal and in the same direction as the man’s push.

C. less than and in the same direction as the man’s push.

D. more than and in the opposite direction as the man’s push

Answer 4

A. equal and in the opposite direction as the man’s push.

Question 5

A skydiver has reached terminal velocity—she now falls at a constant speed, so her acceleration is zero. Is there a net force on her? If so, what is the direction?

A. There is a net force directed upward.

B. There is no net force.

C. There is a net force directed downward.

Answer 5

B. There is no net force.

Question 6

Two people of equal mass on slippery ice are standing still and then push off from each other. Will both move at the same speed in opposite directions?

A. Yes

B. Yes, but only if both push equally.

C. No

Answer 6

A. Yes

Question 7

You are riding in an elevator that is accelerating upward. Suppose you stand on a scale. The reading on the scale is

A. Greater than your true weight.

B. Equal to your true weight.

C. Less than your true weight.

Answer 7

A. Greater than your true weight

Question 8

In general, the coefficient of static friction is

A. Smaller than the coefficient of kinetic friction.

B. Equal to the coefficient of kinetic friction.

C. Greater than the coefficient of kinetic friction.

Answer 8

C. Greater than the coefficient of kinetic friction.

Question 9

The drag force pushes opposite your motion as you ride a bicycle. If you double your speed, what happens to the magnitude of the drag force?

A. The drag force will double

B. The drag force will quadruple.

C. The drag force stays the same.

D. The drag force decreases.

Answer 9

B. The drag force will quadruple.

Question 10

A box is being pulled to the right at steady speed by a rope that angles upward. In this situation:

A. n is greater than mg

B. n is equal to mg

C. n is less than mg

D. n is equal to 0

Answer 10

C. n is less than mg

Question 11

A box with a weight of 100 N is at rest. It is then pulled by a 30 N horizontal force.

The coefficient of static and kinetic friction are listed below.

Does the box move?

Answer 11

No

Question 12

A box is being pulled to the right over a rough surface with tension T, where
T > fk. So the box is speeding up. Suddenly the rope breaks.

What happens? The box

A. Stops immediately.

B. Continues with the speed it had when the rope broke.

C. Continues speeding up for a short while, then slows and stops.

D. Keeps its speed for a short while, then slows and stops.

E. Slows steadily until it stops.

Answer 12

E. Slows steadily until it stops.

Question 13

A ring, seen from above, is pulled on by three forces. The ring is not moving. How big is the force F?

A. 20 N

B. 10 cos ϴ (in N)

C. 10 sin ϴ (in N)

D. 20 cos ϴ (in N)

E. 20 sin ϴ (in N)

Answer 13

E. 20 sin ϴ (in N)

Question 14

If you are not wearing a seat belt and the car you are driving hits a fixed barrier, you will hit the steering wheel with some force. This is because

A. The force of the collision has thrown you forward.

B. The steering wheel has been pushed back toward you.

C. You continue moving even after the car has stopped.

Answer 14

C. You continue moving even after the car has stopped.

Question 15

If you stand on a trampoline, it depresses under your weight. When you stand on a hard stone floor, what happens?

A. The floor does not deform under your weight; it is too stiff.

B. The floor deforms—very slightly—under your weight.

C. The floor deforms a slight amount if you are heavy enough.

Answer 15

B. The floor deforms—very slightly—under your weight.

Question 16

An elevator, lifted by a cable, is moving upward and slowing. What is the correct free-body diagram?

Answer 16

Question 17

A car is parked on a hill. What is the correct free-body diagram?

Answer 17

Question 18

When the man pushes a refrigerator across a kitchen floor at a constant speed, the force of friction between the refrigerator and the floor is

A. equal and in the opposite direction as the man’s push.

B. equal and in the same direction as the man’s push.

C. less than and in the same direction as the man’s push.

D. more than and in the opposite direction as the man’s push

Answer 18

A. equal and in the opposite direction as the man’s push.

Question 19

Consider a high-speed bus colliding head-on with a flying bug. The force of impact splatters the unfortunate bug over the windshield.

Which is greater, the force on the bug or the force on the bus?

A. Bug

B. Bus

C. Both are the same amount.

Answer 19

C. Both are the same amount.

Question 20

When you step off a curb, Earth pulls you downward. The reaction to this force is

A. slight air resistance.

B. you pulling Earth upward.

C. there is no reaction to this force.

Answer 20

B. you pulling Earth upward.

Question 21

Two people of equal mass on slippery ice are standing still and then push off from each other. Will both move at the same speed in opposite directions?

A. Yes

B. Yes, but only if both push equally.

C. No

Answer 21

A. Yes

Question 22

When a cannon is fired, the accelerations of the cannon and cannonball are different because the:

A. forces don’t occur at the same time.

B. forces, although theoretically the same, in practice are not.

C. masses are different.

D. ratios of force to mass are the same.

Answer 22

C. masses are different.

Question 23

A skydiver has reached terminal velocity—she now falls at a constant speed, so her acceleration is zero. Is there a net force on her? If so, what is the direction?

A. There is a net force directed upward.

B. There is no net force.

C. There is a net force directed downward.

Answer 23

B. There is no net force.

Question 24

The acceleration vector of a particle in projectile motion

A. Points along the path of the particle.

B. Points horizontally at all times.

C. Vanishes at the particle’s highest point.

D. Points down at all times.

E. Is zero.

Answer 24

D. Points down at all times.

Question 25

The acceleration vector of a particle in uniform circular motion A. Is zero. B. Points toward the center of the circle. C. Points outward from the center of the circle. D. Points tangent to the circle, in the direction of motion. E. Points tangent to the circle, opposite the direction of motion.

Answer 25

B. Points toward the center of the circle.

Question 26

A factory conveyor belt rolls at 3 m/s. A mouse sees a piece of cheese directly across the belt and heads straight for the cheese at 4 m/s. What is the mouse’s speed relative to the factory floor?

Answer 26

5 m/s

Question 27

Consider the two cars movements below. Both have the same time interval between photos. Which car, A or B, is going slower?

Answer 27

A

Question 28

How many significant figures does this number have? 0.00673

Answer 28

3

Question 29

How many significant figures does this number have? 0.9510

Answer 29

4

Question 30

Which position diagram shows a car slowing down? Remember, the car positions are taken at equal time intervals.

Answer 30

C

Question 31

Consider the motion diagram below of a car moving along a straight road. What is the velocity graph that matches the motion of the car?

Answer 31

Question 32

Consider the motion diagram below of a car moving along a straight road. What is the velocity graph that matches the motion of the car?

Answer 32

Question 33

The graph below is a velocity versus time for a hockey puck shot into a goal. What position graph matches the velocity graph?

Answer 33

Question 34

A ball moves to the left and is slowing down. What is the sign of acceleration? A. Positive B. Negative

Answer 34

A. Positive

Question 35

In rotational motion, θ is positive when measured [ ] from the positive x-axis.

Answer 35

counterclockwise (CCW)

Question 36

In rotational motion, θ is negative when measured [ ] from the positive x-axis.

Answer 36

clockwise (CW)

Question 37

In rotational motion, which unit represents arc length?

Answer 37

The arc length, s, is the distance that the particle has traveled along its circular path.

Question 38

Define angular velocity (omega, w)

Answer 38

Angular velocity is the angular displacement through which the particle moves each second

Question 39

1 mi = ? m

Answer 39

1 mi = 1609 m

Question 40

In rotational motion, how is 1 revolution measured?

Answer 40

2pi

Question 41

Torque (τ) is the rotational equivalent of

Answer 41

force.

Question 42

Torque is in units of

Answer 42

newton-meters, N × m.

Question 43

[ ] is the line starting at the pivot and extending through the point where force is applied.

Answer 43

Radial Line

Question 44

A torque causes an angular

Answer 44

acceleration.

Question 45

The moment of inertia is the rotational equivalent of

Answer 45

mass.

Question 46

What is Newton's second law of rotation?

Answer 46

If more than one torque acts on a rigid body about a fixed axis, then the sum of the torques equals the moment of inertia times the angular acceleration

Question 47

Two conditions for static equilibrium on an extended object:

Answer 47

* The net force on the object must be zero. * The net torque on the object must be zero.

Question 48

A car is turning a corner at a constant speed, following a segment of a circle. What force provides the necessary centripetal acceleration? A. Gravity B. Normal Force C. Static Friction D. Kinetic Friction

Answer 48

C. Static Friction

Question 49

A ball at the end of a string is being swung in a horizontal circle. What force is producing the centripetal acceleration of the ball? Gravity Air resistance Normal force Tension in the string

Answer 49

Tension in the string

Question 50

A ball at the end of a string is being swung in a horizontal circle. What is the direction of the net force on the ball? Tangent to the circle Toward the center of the circle Away from the center of the circle There is no net force

Answer 50

Toward the center of the circle

Question 51

Astronauts on the International Space Station are weightless because There’s no gravity in outer space. The net force on them is zero. The centrifugal force balances the gravitational force. g is very small, although not zero. They are in free fall.

Answer 51

They are in free fall.

Question 52

A passenger on a carnival ride rides in a car that spins in a horizontal circle as shown below. At the instant shown, which arrow gives the direction of the net force on one of the riders? A. B. C. D.

Answer 52

D

Question 53

If an object is rotating clockwise, this corresponds to a ______ angular velocity. Positive Negative

Answer 53

Negative

Question 54

The fan blade is slowing down. What are the signs of ω and α? ω is positive and α is positive. ω is positive and α is negative. ω is negative and α is positive. ω is negative and α is negative. ω is positive and α is zero.

Answer 54

ω is negative and α is positive.

Question 55

The fan blade is speeding up. What are the signs of w and α? ω is positive and α is positive. ω is positive and α is negative. ω is negative and α is positive. ω is negative and α is negative. ω is positive and α is zero.

Answer 55

ω is negative and α is negative

Question 56

The four forces shown have the same strength. Which force would be most effective in opening the door? Force F1 Force F2 Force F3 Force F4

Answer 56

Force F1

Question 57

A net torque applied to an object causes A linear acceleration of the object. The object to rotate at a constant rate. The angular velocity of the object to change. The moment of inertia of the object to change.

Answer 57

The angular velocity of the object to change.

Question 58

Two coins rotate on a turntable. Coin B is twice as far from the axis as coin A. The angular velocity of A is twice that of B The angular velocity of A equals that of B The angular velocity of A is half that of B

Answer 58

The angular velocity of A equals that of B

Question 59

Two coins rotate on a turntable. Coin B is twice as far from the axis as coin A. Which coin has the larger linear (tangential) velocity? A B They have the same linear velocity

Answer 59

B

Question 60

Two spheres have the same radius and equal masses. One is made of solid aluminum and the other is made of a hollow shell of gold. Which sphere has the bigger moment of inertia about an axis through its center? Solid Aluminum Sphere Hollow Gold Sphere They have the same moment of inertia

Answer 60

Hollow Gold Sphere

Question 61

An object is in equilibrium if Fnet = 0 τnet = 0 Either A or B Both A and B

Answer 61

Both A and B

Question 62

The scale is positioned half-way between the mass and the pivot point. What does the scale read? 500 N 1000 N 2000 N 4000 N

Answer 62

2000 N

Question 63

An object will be stable if Its center of gravity is below its highest point. Its center of gravity lies over its base of support. Its center of gravity lies outside its base of support. The height of its center of gravity is less than 1/2 its total height.

Answer 63

Its center of gravity lies over its base of support.

Question 64

The restoring force of three springs is measured as they are stretched. Which spring has the largest spring constant? A B C

Answer 64

A

Question 65

A very rigid material—one that stretches or compresses only slightly under large forces—has a large value of Tensile strength. Elastic limit. Density. Young’s modulus.

Answer 65

Young’s modulus.

Question 66

A person stands on a very light rigid board that rests on a bathroom scale at each end. The left scale reads 35 lbs and the right scale reads 105 lbs. What is the weight of the person? 70 lbs 105 lbs 140 lbs 185 lbs

Answer 66

140 lbs

Question 67

A light plastic cart and a heavy steel cart are both pushed with the same force for 1.0 s, starting from rest. After the force is removed, the momentum of the light plastic cart is ________ that of the heavy steel cart. Greater than Equal to Less than

Answer 67

Equal to

Question 68

A 10 kg cart moves to the left with a velocity of 2 m/s, hits a wall and then moves back toward the right with a velocity of 1 m/s. What is the change of momentum Δp that the cart experiences? –20 kg m/s –10 kg m/s 0 kg m/s 10 kg m/s 30 kg m/s

Answer 68

30 kg m/s

Question 69

Consider a dish falling to the ground. What can you say about the change in momentum when it falls on a carpet verses a hard floor? The change in momentum is less on the carpet The change in momentum is more on the carpet The change in momentum is the same for both carpet and floor

Answer 69

The change in momentum is the same for both carpet and floor

Question 70

The 1-kg box is sliding along a frictionless surface. It collides with and sticks to the 2-kg box. Afterward, the speed of the two boxes is 0 m/s 1 m/s 2 m/s 3 m/s

Answer 70

1 m/s

Question 71

The two boxes are sliding along a frictionless surface. They collide and stick together. Afterward, the velocity of the two boxes is 2 m/s to the left 1 m/s to the left 0 m/s, at rest 1 m/s to the right 2 m/s to the right

Answer 71

0 m/s, at rest

Question 72

The two boxes are on a frictionless surface. They were sitting together at rest, but an explosion between them has just pushed them apart. The 1 kg box moves to the left at 4 m/s. How fast is the 2-kg box going? 1 m/s 2 m/s 4 m/s 8 m/s

Answer 72

2 m/s

Question 73

A mosquito and a truck have a head-on collision. Splat! Which has a larger change of momentum? The mosquito The truck They have the same change of momentum.

Answer 73

They have the same change of momentum.

Question 74

You awake in the night to find that your living room is on fire. Your one chance to save yourself is to throw something that will hit the back of your bedroom door and close it, giving you a few seconds to escape out the window. You happen to have both a sticky ball of clay and a super-bouncy Superball next to your bed, both the same size and same mass. You’ve only time to throw one. Which will it be? Throw the Superball. Throw the ball of clay. It doesn’t matter. Throw either.

Answer 74

Throw the Superball.

Question 75

An object’s angular momentum is proportional to its Mass. Moment of inertia. Kinetic energy. Linear momentum.

Answer 75

Moment of inertia.

Question 76

A child is on a playground swing, motionless at the highest point of his arc. What energy transformation takes place as he swings back down to the lowest point of his motion? K ⇒ Ug Ug ⇒ K Eth ⇒ K Ug ⇒ Eth K ⇒ Eth

Answer 76

Ug ⇒ K

Question 77

Both skiers push off with a Force of 500 N. Which skier will be faster at the bottom of the hill? Red Skier Blue Skier They will have the same speed

Answer 77

Blue Skier

Question 78

A tow rope pulls a skier up the slope at constant speed. What energy transfer (or transfers) is/are taking place? W ⇒ Ug W ⇒ K W ⇒ Eth Both A and B. Both A and C.

Answer 78

Both A and C.

Question 79

Starting from rest, two identical marbles each roll down a frictionless hill both of which are at the same height. One hill is more steep than the other as shown below. Which marble is going faster at the bottom? The marble going down the steeper hill is faster. The marble going down the less steep hill is faster. Both marbles have the same speed at the bottom.

Answer 79

Both marbles have the same speed at the bottom.

Question 80

c A hockey puck sliding on smooth ice at 4 m/s comes to a 1-m-high hill. Will it make it to the top of the hill? Yes. No.

Answer 80

No.

Question 81

Three balls are thrown from a cliff with the same speed but at different angles. Which ball has the greatest speed just before it hits the ground? Ball A. Ball B. Ball C. All balls have the same speed.

Answer 81

All balls have the same speed.

Question 82

Four students run up the stairs in the time shown. Which student has the largest power output? A. B. C. D.

Answer 82

B.

Question 83

Each of the 1.0 kg boxes starts at rest and is then pulled for 2.0 m across a level, frictionless floor by a rope with the noted force and angle. Which box has the highest final speed?

Answer 83

B.

Question 84

If you raise an object to a greater height, you are increasing Kinetic energy. Heat. Potential energy. Chemical energy. Thermal energy.

Answer 84

Potential energy.

Question 85

If you hold a heavy weight over your head, the work you do Is greater than zero. Is equal to zero. Is less than zero. Is converted into chemical energy. Is converted into potential energy.

Answer 85

Is equal to zero.

Question 86

Which of the following is an energy transfer? Kinetic energy Work Potential energy Chemical energy Thermal energy

Answer 86

Work

Question 87

A person throws a javelin into the air. As she propels it forward from rest, she does 270 J of work on it. At its highest point, its gravitational potential energy has increased by 70 J. What is the javelin’s kinetic energy at this point? 270 J 340 J 200 J –200 J –340 J

Answer 87

200 J

Question 88

The following pairs of temperatures represent the temperatures of hot and cold reservoirs for heat engines. Which heat engine has the highest possible efficiency? 300°C, 30°C 250°C, 30°C 200°C, 20°C 100°C, 10°C 90°C, 0°C

Answer 88

300°C, 30°C

Question 89

The efficiency of this heat engine is 1.00 0.60 0.50 0.40 0.20

Answer 89

0.40

Question 90

A large –20°C ice cube is dropped into a super-insulated container holding a small amount of 5°C water, then the container is sealed. Ten minutes later, the temperature of the ice (and any water that has melted from the ice) will be warmer than –20°C. This is a consequence of The first law of thermodynamics. The second law of thermodynamics. The third law of thermodynamics. Both the first and the second laws.

Answer 90

The second law of thermodynamics.

Question 91

When you walk at a constant speed on level ground, what energy transformation is taking place? Echem → Ug Ug → Eth Echem → K Echem → Eth K → Eth

Answer 91

Echem → Eth

Question 92

A machine uses 1000 J of electric energy to raise a heavy mass, increasing its potential energy by 300 J. What is the efficiency of this process? 100% 85% 70% 35% 30%

Answer 92

30%

Question 93

Define isolated system

Answer 93

An isolated system is a system with no net external force acting on it, leaving the momentum unchanged.

Question 94

Answer 94

p2 = p3 > p1

Question 95

Answer 95

B. II

Question 96

A heavy lead block and a light aluminum block of equal sizes are both submerged in water. Upon which is the buoyant force greater? On the lead block On the aluminum block They both experience the same buoyant force.

Answer 96

They both experience the same buoyant force.

Question 97

When taking a patient’s blood pressure, it is usually taken at the arm and is held at about the same height as her heart. If you took your blood pressure at your ankle what would it be relative to your arm? Higher Lower The same

Answer 97

Higher

Question 98

Answer 98

C. They are equal in weight

Question 99

Answer 99

B. decrease by 101.3 kPa

Question 100

Two blocks are of identical size. One which is made of lead sits on the bottom of a pond. The other which is made of wood floats on top. Upon which is the buoyant force greater? On the lead block On the wood block They both experience the same buoyant force

Answer 100

On the lead block

Question 101

Block a Block b Block c All have the same buoyant force. Blocks a and c experience the same buoyant force.

Answer 101

All have the same buoyant force.

Question 102

Answer 102

v1 less than v2

Question 103

Answer 103

P1 greater than P2

Question 104

Answer 104

P1 less than P2

Question 105

What type of function describes simple harmonic motion? Linear. Exponential. Quadratic. Sinusoidal.

Answer 105

Sinusoidal.

Question 106

A ball on a massless, rigid rod oscillates as a simple pendulum with a period of 2.0 s. If the ball is replaced with another ball having twice the mass, the period will be 1.0 s 2.0 s 2.8 s 4.0 s

Answer 106

2.0 s

Question 107

Answer 107

C

Question 108

Answer 108

C

Question 109

Answer 109

A and E

Question 110

Answer 110

Mass A

Question 111

Answer 111

A, C, E

Question 112

Answer 112

B and D

Question 113

Answer 113

A, C, E

Question 114

A typical earthquake produces vertical oscillations of the earth. Suppose a particular quake oscillates the ground at a frequency of 0.15 Hz. As the earth moves up and down, what time elapses between the highest point of the motion and the lowest point? 1.0 s 3.3 s 6.7 s 13 s

Answer 114

3.3 s

Question 115

14 cm 16 cm 20 cm 24 cm

Answer 115

14 cm

Question 116

Answer 116

1.0 s

Question 117

Which of the following is a longitudinal wave? Sound wave Water wave Light wave

Answer 117

Sound wave

Question 118

2.0 Hz 1.5 Hz 1.0 Hz 0.5 Hz

Answer 118

0.5 Hz

Question 119

Which has a longer wavelength? 400-Hz sound wave in air 400-Hz sound wave in water

Answer 119

400-Hz sound wave in water

Question 120

Answer 120

2.0 m

Question 121

Answer 121

100 Hz

Question 122

Answer 122

2.0 s

Question 123

We measure the sound intensity level in units of Watts. Joules. Hertz. Decibels.

Answer 123

Decibels.

Question 124

A 100 Hz sound wave is traveling through the air. If we increase the frequency to 200 Hz, this will ________ the wavelength. Increase Not change Decrease

Answer 124

Decrease

Question 125

Which of the following is a longitudinal wave? Sound wave Water wave Light wave

Answer 125

Sound wave

Question 126

Answer 126

D. 0.5 Hz

Question 127

Answer 127

C. 1.0 m

Question 128

Answer 128

B. 5

Question 129

Answer 129

C

Question 130

An open-closed tube of air of length L has the closed end on the right. Which graph shows the m = 3 standing wave in this tube?

Answer 130

C

Question 131

An open-open tube of air has length L. Which graph shows the m = 3 standing wave in this tube?

Answer 131

A

Question 132

The interference of two sound waves of similar amplitude but slightly different frequencies produces a loud-soft-loud oscillation we call Constructive and destructive interference. The Doppler effect. Beats. Vibrato.

Answer 132

Beats.

Question 133

For a standing wave in a tube open at each end, the open ends of the tube are Nodes Antinodes Modes Beats

Answer 133

Nodes

Question 134

A 170 Hz sound wave in air has a wavelength of 2.0 m. The frequency is now doubled to 340 Hz. What is the new wavelength? 4.0 m 3.0 m 2.0 m 1.0 m

Answer 134

1.0 m

Question 135

A point on a standing wave that is always stationary is a Mode Maximum Node Antinode

Answer 135

Node