Question 1

A physicist and a chemist are playing tug-of-war. For a certain length of time during the game, the participants are essentially at rest. During this time, each person pulls on the rope (which can be treated as an ideal string) with a force of $350 \mathrm{~N}$. What is the tension on the rope?
A) $700 \mathrm{~N}$
B) $350 \mathrm{~N}$
C) $175 \mathrm{~N}$
D) Other (specify)

Accepted Answer

The tension in the rope is $350 \mathrm{~N}$ because the system is in equilibrium (at rest), meaning the forces pulling on either end of the rope are equal and opposite, resulting in a tension equal to the force applied by each person.

Question 2

Object A $\left(m_{A}=1.0 \mathrm{~kg}\right)$ hangs at rest from an ideal string $A$ connected to the ceiling. Object $B\left(m_{B}=2.0 \mathrm{~kg}\right)$ hangs at rest from an ideal string $B$ connected to object $A$. The tension on string $A$ is
A) Twice the tension on string $B$
B) 1.5 times the tension on string $B$
C) Equal to the tension on string $B$
D) $\frac{2}{3}$ the tension on string $B$
E) Other (specify)

Accepted Answer

The tension in string A must support both the weight of object A and object B, while the tension in string B only supports the weight of object B. Therefore, the tension in string A is 1.5 times the tension in string B.

Question 3

A given rope will break if its tension exceeds $360 \mathrm{~N}$. Suppose that each of two people can exert a pull of $200 \mathrm{~N}$. Which strategy below can they use to break that rope?
A) They each take an end and pull.
B) They tie one end to the wall and both pull on the other.
C) They use either of the strategies above.
D) They cannot break the rope.

Accepted Answer

If they tie one end to the wall and both pull on the other end, the total tension in the rope will be $400 \mathrm{~N}$, which exceeds the breaking tension of $360 \mathrm{~N}$.

Question 4

A spring scale typically indicates the magnitude of the tension force exerted on its bottom hook. What will the scale read in each of the cases shown in the diagram? (Hint: Draw a free-body diagram for the scale in each case.)
- 
A) $49 \mathrm{~N}$
B) $98 \mathrm{~N}$
C) $196 \mathrm{~N}$
D) Other (specify)

Accepted Answer

The answer of A spring scale typically indicates the magnitude...

Question 5

A spring scale typically indicates the magnitude of the tension force exerted on its bottom hook. What will the scale read in each of the cases shown in the diagram? (Hint: Draw a free-body diagram for the scale in each case.)
-
A) $49 \mathrm{~N}$
B) $98 \mathrm{~N}$
C) $196 \mathrm{~N}$
D) Other (specify)

Accepted Answer

The answer of A spring scale typically indicates the magnitude...

Question 6

A spring scale typically indicates the magnitude of the tension force exerted on its bottom hook. What will the scale read in each of the cases shown in the diagram? (Hint: Draw a free-body diagram for the scale in each case.)
-
A) $49 \mathrm{~N}$
B) $98 \mathrm{~N}$
C) $196 \mathrm{~N}$
D) Other (specify)

Accepted Answer

The answer of A spring scale typically indicates the magnitude...

Question 7

When a speeding roller-coaster car is at the bottom of a loop, the magnitude of the normal force exerted on the car's wheels due to its interaction with the track is
A) Greater than the weight of the car and its passengers.
B) Equal to the weight of the car and its passengers.
C) Less than the weight of the car and its passengers.

Accepted Answer

At the bottom of a loop, the normal force must not only support the weight of the roller-coaster car and its passengers but also provide the centripetal force necessary to keep the car moving in a circular path. Therefore, the normal force is greater than the weight of the car and its passengers.

Question 8

A child grips tightly the outer edge of a playground merry-go-round as other kids push on it to give it a dizzying rotational velocity. When the other kids let go, the horizontal component of the net force on the child points most nearly
A) Inward toward the center of the merry-go-round.
B) Outward away from the center of the merry-go-round.
C) In the direction of rotation.
D) Nowhere: the net force's horizontal component is zero.
E) In some other direction (specify).

Accepted Answer

The horizontal component of the net force on the child points inward toward the center of the merry-go-round due to centripetal force, which is always directed towards the center of the circular path.

Question 9

A car is traveling counterclockwise along a circular bend in the road whose effective radius is $100 \mathrm{~m}$. At a certain instant of time, the car is traveling due north, has a speed of $10 \mathrm{~m} / \mathrm{s}$, and is in the process of increasing that speed at a rate of $1 \mathrm{~m} / \mathrm{s}^{2}$. The direction of the car's acceleration at that instant is most nearly
A) North
B) Northeast
C) East
D) Northwest
E) West
F) Southwest
G) Zero

Accepted Answer

The answer of A car is traveling counterclockwise along a...

Question 10

A plane in a certain circular holding pattern banks at an angle of $8^{\circ}$ when flying at a speed of $150 \mathrm{mi} / \mathrm{h}$. If a second plane flies in the same circle at $300 \mathrm{mi} / \mathrm{h}$, what is its banking angle?
A) A bit less than $16^{\circ}$
B) Exactly $16^{\circ}$
C) A bit more than $16^{\circ}$
D) A bit less than $32^{\circ}$
E) Exactly $32^{\circ}$
F) A bit more than $32^{\circ}$
G) The answer depends on the planes' masses.

Accepted Answer

The answer of A plane in a certain circular holding...

Question 11

Car 1 with mass $m$ rounds an unbanked curve of radius $R$ traveling at a constant speed $|\vec{v}|$. Car 2 with mass $2 m$ rounds a curve of radius $2 R$ traveling at a constant speed $2|\vec{v}|$. How does the magnitude $\left|\vec{F}_{2}\right|$ of the sideward static friction force acting on car 2 compare with the magnitude $\left|\vec{F}_{1}\right|$ of the sideward static friction force on car 1 ?
A) $\left|\vec{F}_{1}\right|=4\left|\vec{F}_{2}\right|$
B) $\left|\vec{F}_{1}\right|=2\left|\vec{F}_{2}\right|$
C) $\left|\vec{F}_{1}\right|=\left|\vec{F}_{2}\right|$
D) $\left|\vec{F}_{1}\right|=\frac{1}{2}\left|\vec{F}_{2}\right|$
E) $\left|\vec{F}_{1}\right|=\frac{1}{4}\left|\vec{F}_{2}\right|$
F) Other (specify)

Accepted Answer

The answer of Car 1 with mass $m$ rounds an...

Question 12

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 1 ?

A) A
B) B
C) C
D) D
E) E
F) F

Accepted Answer

The answer of  Which one of the arrows below...

Question 13

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 2 ?

A) A
B) B
C) C
D) D
E) E
F) F

Accepted Answer

The answer of 
Which one of the arrows below most...

Question 14

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 3 ?

A) A
B) B
D) D
E) E
F) F

Accepted Answer

The answer of 
Which one of the arrows below most...

Question 15

In a Western movie, a person shoots an arrow backward from a fleeing horse. If the velocity of the horse relative to the ground is $13 \mathrm{~m} / \mathrm{s}$ west and the arrow's velocity relative to the horse is $38 \mathrm{~m} / \mathrm{s}$ east, what is the arrow's velocity with respect to the ground?
A) $41 \mathrm{~m} / \mathrm{s}$ east
B) $41 \mathrm{~m} / \mathrm{s}$ west
C) $25 \mathrm{~m} / \mathrm{s}$ east
D) $25 \mathrm{~m} / \mathrm{s}$ west

Accepted Answer

The arrow's velocity relative to the ground is the sum of the horse's velocity and the arrow's velocity relative to the horse. Since the horse is moving west and the arrow is shot east, the velocities are in opposite directions: $38 \mathrm{~m/s} - 13 \mathrm{~m/s} = 25 \mathrm{~m/s}$ east.

Question 16

A blimp has a velocity of $8.2 \mathrm{~m} / \mathrm{s}$ due west relative to the air. There is a wind blowing at $3.5 \mathrm{~m} / \mathrm{s}$ due north. The speed of the balloon relative to the ground is
A) $11.7 \mathrm{~m} / \mathrm{s}$
B) $8.9 \mathrm{~m} / \mathrm{s}$
C) $7.4 \mathrm{~m} / \mathrm{s}$
D) $4.7 \mathrm{~m} / \mathrm{s}$
E) Some other speed (specify)

Accepted Answer

The speed of the balloon relative to the ground is found by using the Pythagorean theorem: $\sqrt{(8.2)^2 + (3.5)^2} = 8.9 \mathrm{~m} / \mathrm{s}$.

Question 17

An elevator moves downward with an acceleration of $6.2 \mathrm{~m} / \mathrm{s}^{2}$. A ball dropped from rest by a passenger will have what downward acceleration relative to the elevator?
A) $3.6 \mathrm{~m} / \mathrm{s}^{2}$
B) $6.2 \mathrm{~m} / \mathrm{s}^{2}$
C) $9.8 \mathrm{~m} / \mathrm{s}^{2}$
D) $16.0 \mathrm{~m} / \mathrm{s}^{2}$
E) Some other acceleration (specify)

Accepted Answer

The answer of An elevator moves downward with an acceleration...

Question 18

When you go over the crest of a hill in a roller coaster, a force appears to lift you up out of your seat. This is a fictitious force.

Accepted Answer

This sensation is due to a reduction in the normal force exerted on you by the seat as the roller coaster goes over the crest, creating a feeling of weightlessness or being lifted out of the seat, which is often described in terms of fictitious forces in a non-inertial reference frame.

Question 19

If your car is hit from behind, you are suddenly pressed back into the seat. The normal force that the seat exerts on you is a fictitious force.

Accepted Answer

The normal force exerted by the seat on you is a real force that arises due to the contact between your body and the seat, following Newton's third law of motion, not a fictitious force.

Question 20

You are pressed downward toward the floor as an elevator begins to move upward. The force pressing you down is a fictitious force.

Accepted Answer

The force pressing you down is the normal force exerted by the floor on your feet. This force is a real force, not a fictitious force.

Quiz 2: The Laws of Physics Are Universal Newtonian Mechanics

A physicist and a chemist are playing tug-of-war. For a certain length of time during the game, the participants are essentially at rest. During this time, each person pulls on the rope (which can be treated as an ideal string) with a force of $350 \mathrm{~N}$ . What is the tension on the rope?

Object A $\left(m_{A}=1.0 \mathrm{~kg}\right)$ hangs at rest from an ideal string $A$ connected to the ceiling. Object $B\left(m_{B}=2.0 \mathrm{~kg}\right)$ hangs at rest from an ideal string $B$ connected to object $A$ . The tension on string $A$ is

A given rope will break if its tension exceeds $360 \mathrm{~N}$ . Suppose that each of two people can exert a pull of $200 \mathrm{~N}$ . Which strategy below can they use to break that rope?

When a speeding roller-coaster car is at the bottom of a loop, the magnitude of the normal force exerted on the car's wheels due to its interaction with the track is

A child grips tightly the outer edge of a playground merry-go-round as other kids push on it to give it a dizzying rotational velocity. When the other kids let go, the horizontal component of the net force on the child points most nearly

A plane in a certain circular holding pattern banks at an angle of $8^{\circ}$ when flying at a speed of $150 \mathrm{mi} / \mathrm{h}$ . If a second plane flies in the same circle at $300 \mathrm{mi} / \mathrm{h}$ , what is its banking angle?

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 1 ?

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 2 ?

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 3 ? A) A B) B D) D E) E F) F

A blimp has a velocity of $8.2 \mathrm{~m} / \mathrm{s}$ due west relative to the air. There is a wind blowing at $3.5 \mathrm{~m} / \mathrm{s}$ due north. The speed of the balloon relative to the ground is

An elevator moves downward with an acceleration of $6.2 \mathrm{~m} / \mathrm{s}^{2}$ . A ball dropped from rest by a passenger will have what downward acceleration relative to the elevator?

When you go over the crest of a hill in a roller coaster, a force appears to lift you up out of your seat. This is a fictitious force.

If your car is hit from behind, you are suddenly pressed back into the seat. The normal force that the seat exerts on you is a fictitious force.

You are pressed downward toward the floor as an elevator begins to move upward. The force pressing you down is a fictitious force.

Quiz 2: The Laws of Physics Are Universal Newtonian Mechanics

A given rope will break if its tension exceeds 360 N360 \mathrm{~N}360 N . Suppose that each of two people can exert a pull of 200 N200 \mathrm{~N}200 N . Which strategy below can they use to break that rope?

A spring scale typically indicates the magnitude of the tension force exerted on its bottom hook. What will the scale read in each of the cases shown in the diagram? (Hint: Draw a free-body diagram for the scale in each case.) -

A spring scale typically indicates the magnitude of the tension force exerted on its bottom hook. What will the scale read in each of the cases shown in the diagram? (Hint: Draw a free-body diagram for the scale in each case.) -

A spring scale typically indicates the magnitude of the tension force exerted on its bottom hook. What will the scale read in each of the cases shown in the diagram? (Hint: Draw a free-body diagram for the scale in each case.) -

When a speeding roller-coaster car is at the bottom of a loop, the magnitude of the normal force exerted on the car's wheels due to its interaction with the track is

A child grips tightly the outer edge of a playground merry-go-round as other kids push on it to give it a dizzying rotational velocity. When the other kids let go, the horizontal component of the net force on the child points most nearly

A plane in a certain circular holding pattern banks at an angle of 8∘8^{\circ}8∘ when flying at a speed of 150mi/h150 \mathrm{mi} / \mathrm{h}150mi/h . If a second plane flies in the same circle at 300mi/h300 \mathrm{mi} / \mathrm{h}300mi/h , what is its banking angle?

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 1 ?

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 2 ?

Which one of the arrows below most closely indicates the direction of the bob's acceleration when it is at point 3 ? A) A B) B D) D E) E F) F

A blimp has a velocity of 8.2 m/s8.2 \mathrm{~m} / \mathrm{s}8.2 m/s due west relative to the air. There is a wind blowing at 3.5 m/s3.5 \mathrm{~m} / \mathrm{s}3.5 m/s due north. The speed of the balloon relative to the ground is

An elevator moves downward with an acceleration of 6.2 m/s26.2 \mathrm{~m} / \mathrm{s}^{2}6.2 m/s2 . A ball dropped from rest by a passenger will have what downward acceleration relative to the elevator?

When you go over the crest of a hill in a roller coaster, a force appears to lift you up out of your seat. This is a fictitious force.

If your car is hit from behind, you are suddenly pressed back into the seat. The normal force that the seat exerts on you is a fictitious force.

You are pressed downward toward the floor as an elevator begins to move upward. The force pressing you down is a fictitious force.

A given rope will break if its tension exceeds $360 \mathrm{~N}$ . Suppose that each of two people can exert a pull of $200 \mathrm{~N}$ . Which strategy below can they use to break that rope?

A plane in a certain circular holding pattern banks at an angle of $8^{\circ}$ when flying at a speed of $150 \mathrm{mi} / \mathrm{h}$ . If a second plane flies in the same circle at $300 \mathrm{mi} / \mathrm{h}$ , what is its banking angle?

A blimp has a velocity of $8.2 \mathrm{~m} / \mathrm{s}$ due west relative to the air. There is a wind blowing at $3.5 \mathrm{~m} / \mathrm{s}$ due north. The speed of the balloon relative to the ground is

An elevator moves downward with an acceleration of $6.2 \mathrm{~m} / \mathrm{s}^{2}$ . A ball dropped from rest by a passenger will have what downward acceleration relative to the elevator?