Question 1

The graph in Figure 2-5 plots the velocity of two cars (A and B) along the same straight road.
Figure 2-5

During the time interval shown, which car is AHEAD?
A) Car A
B) Car B
C) insufficient information

Accepted Answer

The answer of The graph in Figure 2-5 plots the...

Question 2

The graph in Figure 2-6 plots the velocity of two cars (A and B) along the same straight road.
Figure 2-6

Which car reverses direction?
A) Car A
B) insufficient information
C) Car B
D) both cars A & B 
E) neither car A nor B

Accepted Answer

The answer of The graph in Figure 2-6 plots the...

Question 3

Refer to Figure 2-7:
Figure 2-7
 
During the first 8 s
A) D is speeding up while C is slowing down
B) their accelerations are equal in magnitude, but opposite in sign.
C) their accelerations are equal in magnitude, and equal in sign.
D) the magnitude of the acceleration of C is greater than the magnitude of the acceleration of D.
E) the magnitude of the acceleration of D is greater than the magnitude of the acceleration of C.

Accepted Answer

The answer of Refer to Figure 2-7:
Figure 2-7
 
During the...

Question 4

A car is able to stop in a distance d. Assuming the same braking force, what distance does this car require to stop when it is traveling twice as fast?
A) 4 d
B) d
C)  d
D) 2  d
E) 2 d

Accepted Answer

The answer of A car is able to stop in...

Question 5

A can, after having been given a kick, moves up along a smooth hill of ice. It will
A) have a constant acceleration up the hill, but a smaller constant acceleration when it comes back down the hill.
B) have a constant acceleration up the hill, but a larger constant acceleration when it comes back down the hill.
C) have the same acceleration, both up the hill and down the hill.
D) have a varying acceleration along the hill.
E) travel at constant velocity.

Accepted Answer

The acceleration due to gravity remains constant regardless of the can's direction of motion, up or down the hill.

Question 6

Which physical unit is the SI acceleration of gravity? A) 32 ft/s² B) -120 mi/s C) 186,000 mi D) 40 km, SW E) 9.8 m/s²

Accepted Answer

The SI unit for acceleration, including the acceleration due to gravity, is meters per second squared (m/s^2). Option E, 9.8 m/s^2, correctly represents the average acceleration due to gravity at Earth's surface.

Question 7

Which physical unit represents acceleration in the British system? A) 32 ft/s² B) -120 mi/s C) 40 km, SW D) 186,000 mi E) 9.8 m/s²

Accepted Answer

Acceleration is defined as the rate of change of velocity with respect to time. In the British system, acceleration is typically expressed in feet per second squared (ft/s^2). Choice A, "32 ft/s^2", correctly represents an acceleration unit in the British system.

Question 8

When an object is released from rest and falls in the absence of friction, which of the following is true concerning its motion?
A) Neither its acceleration nor its velocity is constant.
B) Both its acceleration and its velocity are constant.
C) Its acceleration is constant.
D) Its velocity is constant.

Accepted Answer

Its acceleration is constant due to the constant acceleration of gravity, assuming negligible air resistance.

Question 9

When a ball is thrown straight up, which of the following is zero at its highest point?
A) displacement
B) acceleration
C) velocity

Accepted Answer

At the highest point of its trajectory, the velocity of the ball is zero because it momentarily stops moving upward before starting to fall back down. The acceleration due to gravity is not zero; it continues to act downward, and displacement refers to the ball's position relative to its starting point, not its speed or acceleration.

Question 10

When a ball is thrown straight up, the acceleration at its highest point is
A) horizontal.
B) minimum.
C) downward.
D) zero.
E) upward.

Accepted Answer

The acceleration of a ball thrown straight up is always directed downward due to gravity, even at its highest point where its velocity is momentarily zero.

Question 11

A ball is thrown straight up and returns to its starting point under an acceleration due to gravity. Which of the following is true?
A) To compare rise and fall times we need to know the mass of the ball.
B) It took the same time to rise as it took to fall.
C) It took less time to rise than to fall.
D) It took longer to rise than to fall.

Accepted Answer

The time it takes for an object to rise to its highest point when thrown straight up is equal to the time it takes to fall back to its starting point, assuming no air resistance and a constant acceleration due to gravity.

Question 12

A race car circles 10 times around an 8-km track in 20 min. What is its average speed per lap?

Accepted Answer

The answer of A race car circles 10 times around...

Question 13

Denis swims the length of a 40. meter pool in 10. seconds and immediately swims back to the starting position in another 15. seconds. What was his average speed?

Accepted Answer

The answer of Denis swims the length of a 40....

Question 14

A race car circles 10 times around an 8-km track in 20 min. What is its average velocity per lap?

Accepted Answer

The answer of A race car circles 10 times around...

Question 15

Jane walks 31 steps eastward and 16 steps southward. What is her displacement if each step averages 0.82 meters?

Accepted Answer

The answer of Jane walks 31 steps eastward and 16...

Question 16

Eric watches a jet powered truck during an "air-show." It accelerates from rest to 300. mph in 8.0 seconds. The acceleration was equivalent to how many "g's"?

Accepted Answer

The answer of Eric watches a jet powered truck during...

Question 17

A car traveling 60 km/h accelerates at the rate of 4.0 m/s². How much time is required for the car to reach a speed of 90 km/h?

Accepted Answer

The answer of A car traveling 60 km/h accelerates at...

Question 18

Captain Rickard orders his starship to accelerate from rest at a rate of "1g" (accel = 9.8 m/s²). How long does it take the starship to reach one-tenth the speed of light if light travels 300. megameters/s?

Accepted Answer

The answer of Captain Rickard orders his starship to accelerate...

Question 19

A bat, flying due east at 2 m/s, emits a shriek that is reflected back to it from an oncoming insect flying directly toward the bat at 4 m/s. The insect is 20 m from the bat at the instant the shriek is emitted. Sound travels 340 m/s in air. After what elapsed time does the bat hear the reflected echo?

Accepted Answer

The answer of A bat, flying due east at 2...

Question 20

A bullet moving at 244. m/s strikes a tree and penetrates a distance of 8.34 mm before stopping. What was the average acceleration of the bullet as it slowed?

Accepted Answer

The answer of A bullet moving at 244. m/s strikes...

Quiz 2: Kinematics: Description of Motion

The graph in Figure 2-5 plots the velocity of two cars (A and B) along the same straight road. Figure 2-5 During the time interval shown, which car is AHEAD?

The graph in Figure 2-6 plots the velocity of two cars (A and B) along the same straight road. Figure 2-6 Which car reverses direction?

Refer to Figure 2-7: Figure 2-7 During the first 8 s

A car is able to stop in a distance d. Assuming the same braking force, what distance does this car require to stop when it is traveling twice as fast?

A can, after having been given a kick, moves up along a smooth hill of ice. It will

Which physical unit is the SI acceleration of gravity?

Which physical unit represents acceleration in the British system?

When an object is released from rest and falls in the absence of friction, which of the following is true concerning its motion?

When a ball is thrown straight up, which of the following is zero at its highest point?

When a ball is thrown straight up, the acceleration at its highest point is

A ball is thrown straight up and returns to its starting point under an acceleration due to gravity. Which of the following is true?