Deck 2: Force and Newtons Laws of Motion, Oscillations, Gravitation, Work and Energy

Question 1

On its own, a tow truck has a maximum acceleration of 3.0 m/s^-2. What would be the maximum acceleration when the truck was towing a bus of twice its own mass?

A) 2.5 m/s^-2
B) 2.0 m/s^-2
C) 1.5 m/s^-2
D) 1.0 m/s^-2

Answer 1

1.0 m/s^-2

Question 2

The figure shows an object's acceleration-versus-force graph. What is the object's mass in grams?

A) 2.5
B) 1.6
C) 630
D) 400,000

Answer 2

2.5

Question 3

The figure shows two forces acting on an object. They have magnitudes F₁ = 6.3 N and
F₂ = 2.1 N. What third force will cause the object to be in equilibrium?

A) 6.6 N at 162° counterclockwise from
B) 6.6 N at 108° counterclockwise from
C) 4.2 N at 162° counterclockwise from
D) 4.2 N at 108° counterclockwise from

Answer 3

6.6 N at 162° counterclockwise from

Question 4

An object accelerates at 4.1 m/s² under the action of two rubber bands. What will be the object's acceleration if it is pulled by four rubber bands?

A) 8.2 m/s²
B) 16 m/s²
C) 4.1 m/s²
D) 2.1 m/s²

Question 5

Consider the following figure. Assume the strings and pulleys have negligible masses and the coefficient of kinetic friction between the 2.0 kg block and the table is 0.25. What is the acceleration of the 2.0 kg block?

A) 2.5 m/s²
B) 1.7 m/s²
C) 3.2 m/s²
D) 4.0 m/s²

Question 6

Consider what happens when you jump up in the air. Which of the following is the most accurate statement?

A) It is the upward force exerted by the ground that pushes you up, but this force can never exceed your weight.
B) You are able to spring up because the earth exerts a force upward on you which is stronger than the downward force you exert on the earth.
C) Since the ground is stationary, it cannot exert the upward force necessary to propel you into the air. Instead, it is the internal forces of your muscles acting on your body itself which propels the body into the air.
D) When you push down on the earth with a force greater than your weight, the earth will push back with the same magnitude force and thus propel you into the air.

Question 7

A dog is standing in the tail bed of a pickup truck. The tail bed is coated with ice, causing the force of friction between the dog and the truck to be zero. The truck is initially at rest, and then accelerates to the right, moving along a flat road. As seen from a stationary observer (watching the truck move to the right), the dog

A) does not move left or right, but simply slides toward the back of the truck.
B) moves to the right, but not as quickly as the truck is moving to the right, causing it to slide toward the back of the truck.
C) moves to the right at the same rate as the truck, so it doesn't slide.
D) moves to the left, as the truck moves to the right, causing the dog to slide toward the back of the truck.

Question 8

Two blocks, A and B, are being pulled to the right along a horizontal surface by a horizontal 100 N pull, as shown in the figure. Both of them are moving together at a constant velocity of 2.0 m/s to the right, and both weigh the same. Which of the figures below shows a correct free-body diagram of the horizontal forces acting on upper block, A?

A)


B)


C)


D)


E)

Question 9

-In the figure, a certain type of string will break if the tension in the string exceeds 300 N. A number of 8-kg weights are hung one below the other from a hook in the ceiling using this string. The number of weights that causes the string to break and the string segment that will break are as follows:

A) When the 4th weight is added, the top string segment will break.
B) Each segment has a tension of 78.4000015 N, and there is no limit to the number of weights that can be suspended.
C) When the 4th weight is added, the bottom string segment will break.
D) When the 4th weight is added, all string segments will break.
E) When the 38th weight is added, all string segments will break.

Question 10

Two blocks, A and B, are being pulled to the right along a horizontal surface by a horizontal 100 N pull, as shown in the figure. Both of them are moving together at a constant velocity of 2.0 m/s to the right, and both weigh the same. Which of the figures below shows a correct free-body diagram of the horizontal forces acting on lower block, B?

A)


B)


C)


D)


E) None of these diagrams is correct.

Question 11

Two cyclists, who weigh the same and have identical bicycles, ride up the same mountain, both starting at the same time. Joe rides straight up the mountain, and Bob rides up the longer road that has a lower grade. Joe gets to the top before Bob. Which statement is true?

A) Ignoring friction and wind resistance, the amount of work done by Joe is equal to the amount of work done by Bob, but the average power exerted by Joe is greater than that of Bob.
B) Ignoring friction and wind resistance, the amount of work done by Joe is greater than the amount of work done by Bob, and the average power exerted by Joe is greater than that of Bob.
C) Ignoring friction and wind resistance, Bob and Joe exerted the same amount of work, and the average power of each cyclist was also the same.
D) Ignoring friction and wind resistance, the average power exerted by Bob and Joe was the same, but Joe exerted more work in getting there.

Question 12

A leaky faucet drips 40 times in 30.0 s. What is the frequency of the dripping?

A) 1.3 Hz
B) 0.75 Hz
C) 1.6 Hz
D) 0.63 Hz

Question 13

A 0.25 kg harmonic oscillator has a total oscillation energy of 4.0 J. If the oscillation amplitude is 20.0 cm, what is the oscillation frequency?

A) 4.5 Hz
B) 1.4 Hz
C) 2.3 Hz
D) 3.1 Hz

Question 14

The length of a pendulum changes by thermal expansion. If the length increases by 0.1%, what would be the change in the period?

A) increase by $\sqrt{1.001}$
B) increase by 0.1%
C) decrease by 0.1%
D) decrease by 0.99

Question 15

At their closest approach, Venus and Earth are 4.20 × 10¹⁰ m apart. The mass of Venus is 4.87 × 10²⁴ kg, the mass of Earth is 5.97 × 10²⁴ kg, and G = 6.67 × 10^-11 N · m²/kg/². What is the force exerted by Venus on Earth at that point?

A) 1.10 × 10¹⁸ N
B) 4.62 × 10²⁸ N
C) 5.43 × 10²⁶ N
D) 6.30 × 10²⁰ N
E) 1.72 × 10¹⁹ N

Question 16

The speed for a "low" circular orbit about the Earth is about

A) 1.7 × 10⁴ km/s.
B) 7.6 km/s.
C) 2.1 km/s.
D) 2.5 × 10⁴ km/s.
E) 17. km/s.