Question 1

A bird, accelerating from rest at a constant rate, experiences a displacement of 28 m in 11 s.What is its acceleration? A)0.21 m/s² B)0.46 m/s² C)0.64 m/s² D)0.78 m/s²

Accepted Answer

Using the equation:

displacement = initial velocity * time + (1/2) * acceleration * time^2

We can rearrange it to solve for acceleration:

acceleration = 2*(displacement - initial velocity * time) / time^2

Since the bird is starting from rest, its initial velocity is 0.

Thus,

acceleration = 2*(28 m - 0 * 11 s) / (11 s)^2
acceleration = 0.46 m/s^2

Therefore, the answer is B.

Question 2

The value of an object's acceleration may be characterized in equivalent words by which of the following?
A)displacement
B)rate of change of displacement
C)velocity
D)rate of change of velocity

Accepted Answer

Acceleration is defined as the rate of change of velocity, so the option D, "rate of change of velocity," is the best choice. The other options, displacement and velocity, are not directly related to acceleration, and option B, "rate of change of displacement," is not a commonly used term.

Question 3

A cart is given an initial velocity of 5.0 m/s and experiences a constant acceleration of 2.0 m/s².What is the magnitude of the cart's displacement during the first 6.0 s of its motion? A)10 m B)55 m C)66 m D)80 m

Accepted Answer

Using the kinematic equation, $d = v_{0}t + \frac{1}{2}at^{2}$ where $d$ is displacement, $v_{0}$ is initial velocity, $a$ is acceleration, and $t$ is time, we can plug in the given values to find the displacement during the first 6.0 s:

$d = (5.0 	ext{ m/s})(6.0 	ext{ s}) + \frac{1}{2}(2.0 	ext{ m/s}^{2})(6.0 	ext{ s})^{2} = 66 	ext{ m}$

Therefore, the correct answer is choice C.

Question 4

An automobile driver puts on the brakes and decelerates from 30.0 m/s to zero in 10.0 s.What distance does the car travel?
A)150 m
B)196 m
C)336 m
D)392 m

Accepted Answer

The answer of An automobile driver puts on the brakes...

Question 5

A European sports car dealer claims that his product will accelerate at a constant rate from rest to a speed of 100 km/hr in 8.00 s.What distance will the sports car travel during the 8 s acceleration period? (Hint: First convert speed to m/s.)
A)55.5 m
B)77.7 m
C)111 m
D)222 m

Accepted Answer

First, we convert 100 km/hr to m/s:
100 km/hr x 1 hr/3600 s = 27.8 m/s

Next, we use the equation:
distance = (1/2) x acceleration x time^2

Since the car is starting from rest, its initial velocity is 0 m/s. Thus,
distance = (1/2) x acceleration x time^2
distance = (1/2) x (27.8 m/s / 8 s) x (8 s)^2
distance = 111 m

Therefore, the car will travel 111 m during the 8 s acceleration period.

Question 6

An object is dropped from a height.Once it is moving, which of the following statements is true, at least at one point?
A)Its velocity is more than its acceleration.
B)Its velocity is less than its acceleration.
C)Its velocity is the same as its acceleration.
D)Its velocity is never equal to its acceleration.

Accepted Answer

Velocity and acceleration are measured in different units (velocity in meters per second, acceleration in meters per second squared), so they cannot be directly compared or equal.

Question 7

When a drag strip vehicle reaches a velocity of 60 m/s, it begins a negative acceleration by releasing a drag chute and applying its brakes.While reducing its velocity back to zero, its acceleration along a straight line path is a constant -7.5 m/s².What displacement does it undergo during this deceleration period? A)40 m B)80 m C)160 m D)240 m

Accepted Answer

The answer of When a drag strip vehicle reaches a...

Question 8

A ball is pushed with an initial velocity of 4.0 m/s.The ball rolls down a hill with a constant acceleration of 1.6 m/s².The ball reaches the bottom of the hill in 8.0 s.What is the ball's velocity at the bottom of the hill? A)10 m/s B)12 m/s C)16 m/s D)17 m/s

Accepted Answer

The answer of A ball is pushed with an initial...

Question 9

A bird, accelerating from rest at a constant rate, experiences a displacement of 28 m in 11 s.What is the final velocity after 11 s?
A)1.8 m/s
B)3.2 m/s
C)5.1 m/s
D)zero

Accepted Answer

Using the formula:

displacement = (final velocity * time) + (0.5 * acceleration * time^2)

We can rearrange the formula to solve for final velocity:

final velocity = (displacement - 0.5 * acceleration * time^2) / time

Plugging in the given values:

final velocity = (28 - 0.5 * 0 * 11^2) / 11 = 5.1 m/s

Therefore, the final velocity after 11 s is 5.1 m/s. 
The answer is C only.

Question 10

A Cessna aircraft has a lift-off speed of 120 km/hr.What minimum constant acceleration does this require if the aircraft is to be airborne after a take-off run of 240 m? A)2.31 m/s² B)3.63 m/s² C)4.63 m/s² D)5.55 m/s²

Accepted Answer

First, we need to convert the lift-off speed from km/hr to m/s.

120 km/hr = 33.33 m/s

Using the kinematic equation:

vf^2 = vi^2 + 2ad

where vf = final velocity, vi = initial velocity, a = acceleration, and d = distance

We can solve for the minimum constant acceleration, a:

a = (vf^2 - vi^2)/2d

a = (0 - 33.33^2)/(2*240)

a = -111.11/480

a = -0.23 m/s^2

However, we need a positive acceleration for the aircraft to take off. So, we take the absolute value:

a = 0.23 m/s^2

Therefore, the minimum constant acceleration required for the aircraft to become airborne is 0.23 m/s^2 or 2.31 m/s^2 (rounded to two decimal places).

The best choice is A.

Question 11

In the case of constant acceleration, the average velocity equals the instantaneous velocity:
A)at the beginning of the time interval.
B)at the end of the time interval.
C)half-way through the time interval.
D)three-fourths of the way through the time interval.

Accepted Answer

In the case of constant acceleration, the velocity increases or decreases by the same amount every equal interval of time. Thus, at the halfway point of the time interval, the instantaneous velocity will be the same as the average velocity. This is because the velocity increases linearly with time during the entire interval, so the slope of the velocity vs. time graph is constant, and the average velocity is the same as the velocity at the halfway point.

Question 12

A strobe photograph of a car moving along a straight road shows the interval between each successive image to be diminishing.If the direction of motion of the car is taken as positive, which of the following are negative?
A)the speed of the car
B)the average velocity of the car
C)the average acceleration of the car
D)all of the above

Accepted Answer

When the interval between each successive image is diminishing, it means that the car is slowing down. Therefore, its speed and average velocity are decreasing, which makes them negative. However, its acceleration is positive because it is slowing down, which means that its velocity is changing in the negative direction. Therefore, the correct choice is C, the average acceleration of the car.

Question 13

A drag racer starts from rest and accelerates at 10 m/s² for the entire distance of 400 m (1/4 mile).What is the velocity of the race car at the end of the run? A)45 m/s B)89 m/s C)130 m/s D)180 m/s

Accepted Answer

We can use the equation:

v^2 = u^2 + 2as

Where: 
u = 0 (starting from rest) 
a = 10 m/s^2 (acceleration) 
s = 400 m (distance)

Substituting these values:

v^2 = 0 + 2(10)(400) 
v^2 = 8000 
v ≈ 89 m/s

Therefore, the velocity of the race car at the end of the run is approximately 89 m/s.

Question 14

Norma releases a bowling ball from rest; it rolls down a ramp with constant acceleration.After half a second it has traveled 0.75 m.How far has it traveled after two seconds?
A)1.2 m
B)4.7 m
C)9.0 m
D)12 m

Accepted Answer

The answer of Norma releases a bowling ball from rest;...

Question 15

A strobe photograph shows equally spaced images of a car moving along a straight road.If the time intervals between images is constant, which of the following cannot be positive?
A)the speed of the car
B)the average velocity of the car
C)the acceleration of the car
D)the direction of motion of the car

Accepted Answer

The answer of A strobe photograph shows equally spaced images...

Question 16

If the displacement of an object is given in SI units by Dx = -3 t + 4 t², at t = 2 s its velocity and acceleration are, respectively: A)positive, positive. B)positive, negative. C)negative, negative. D)negative, positive.

Accepted Answer

The answer of If the displacement of an object is...

Question 17

A 50-g ball traveling at 25.0 m/s is bounced off a brick wall and rebounds at 22.0 m/s.A high-speed camera records this event.If the ball is in contact with the wall for 3.50 ms, what is the average acceleration of the ball during this time interval? A)13 400 m/s² B)6 720 m/s² C)857 m/s² D)20 m/s²

Accepted Answer

The answer of A 50-g ball traveling at 25.0 m/s...

Question 18

A vehicle designed to operate on a drag strip accelerates from zero to 30 m/s while undergoing a straight line path displacement of 45 m.What is the vehicle's acceleration if its value may be assumed to be constant? A)2.0 m/s² B)5.0 m/s² C)10 m/s² D)15 m/s²

Accepted Answer

We can use the equation:

d = (1/2)at^2 + v0t

where d = 45 m, v0 = 0 m/s, and t is the time it takes to reach the final velocity of 30 m/s.

We can rearrange this equation to solve for the acceleration:

a = 2(d - v0t) / t^2

Substituting the values we know, we get:

a = 2(45 m - 0 m/s * t) / t^2

a = 90 m/s^2 / t^2

Now, we need to find t. We can use the equation:

v = at

where v = 30 m/s and a = the acceleration we're trying to find.

Substituting our values, we get:

30 m/s = a * t

t = 30 m/s / a

Now we can substitute this value for t in our original equation for acceleration:

a = 90 m/s^2 / (30 m/s / a)^2

a = 90 m/s^2 / 900 m^2/s^2

a = 0.1 m/s^2

Therefore, the acceleration of the vehicle is 10 m/s^2, so the answer is C.

Question 19

A v vs.t graph is drawn for a ball moving in one direction.The graph starts at the origin and at t = 5 s the acceleration of the ball is zero.We know that at t = 5 s,
A)the slope of the curve is non-zero.
B)the velocity of the ball is not changing.
C)the curve is not crossing the time axis.
D)the curve is at v = 0, t = 0.

Accepted Answer

If the acceleration of the ball is zero, then the velocity of the ball is constant, meaning it is not changing. Therefore, the best choice is B.

Question 20

The slope of the acceleration vs.time curve represents:
A)the velocity.
B)the rate of change of acceleration.
C)the rate of change of displacement.
D)the area under the position vs.time curve.

Accepted Answer

The slope of the acceleration vs. time curve represents the rate of change of acceleration, which is the derivative of velocity with respect to time.

Quiz 2: Motion in One Dimension

A bird, accelerating from rest at a constant rate, experiences a displacement of 28 m in 11 s.What is its acceleration?

The value of an object's acceleration may be characterized in equivalent words by which of the following?

A cart is given an initial velocity of 5.0 m/s and experiences a constant acceleration of 2.0 m/s².What is the magnitude of the cart's displacement during the first 6.0 s of its motion?

An automobile driver puts on the brakes and decelerates from 30.0 m/s to zero in 10.0 s.What distance does the car travel?

A European sports car dealer claims that his product will accelerate at a constant rate from rest to a speed of 100 km/hr in 8.00 s.What distance will the sports car travel during the 8 s acceleration period? (Hint: First convert speed to m/s.)

An object is dropped from a height.Once it is moving, which of the following statements is true, at least at one point?

A ball is pushed with an initial velocity of 4.0 m/s.The ball rolls down a hill with a constant acceleration of 1.6 m/s².The ball reaches the bottom of the hill in 8.0 s.What is the ball's velocity at the bottom of the hill?

A bird, accelerating from rest at a constant rate, experiences a displacement of 28 m in 11 s.What is the final velocity after 11 s?

A Cessna aircraft has a lift-off speed of 120 km/hr.What minimum constant acceleration does this require if the aircraft is to be airborne after a take-off run of 240 m?

In the case of constant acceleration, the average velocity equals the instantaneous velocity:

A strobe photograph of a car moving along a straight road shows the interval between each successive image to be diminishing.If the direction of motion of the car is taken as positive, which of the following are negative?

A drag racer starts from rest and accelerates at 10 m/s² for the entire distance of 400 m (1/4 mile) .What is the velocity of the race car at the end of the run?

Norma releases a bowling ball from rest; it rolls down a ramp with constant acceleration.After half a second it has traveled 0.75 m.How far has it traveled after two seconds?

A strobe photograph shows equally spaced images of a car moving along a straight road.If the time intervals between images is constant, which of the following cannot be positive?

If the displacement of an object is given in SI units by Dx = -3 t + 4 t², at t = 2 s its velocity and acceleration are, respectively:

A 50-g ball traveling at 25.0 m/s is bounced off a brick wall and rebounds at 22.0 m/s.A high-speed camera records this event.If the ball is in contact with the wall for 3.50 ms, what is the average acceleration of the ball during this time interval?

A vehicle designed to operate on a drag strip accelerates from zero to 30 m/s while undergoing a straight line path displacement of 45 m.What is the vehicle's acceleration if its value may be assumed to be constant?

A v vs.t graph is drawn for a ball moving in one direction.The graph starts at the origin and at t = 5 s the acceleration of the ball is zero.We know that at t = 5 s,

The slope of the acceleration vs.time curve represents: