Test Prep
Multiple Choice
3.1 Acceleration
Which variable represents displacement?
- a
- d
- t
- v
If a velocity increases from 0 to 20 m/s in 10 s, what is the average acceleration?
- 0.5 m/s2
- 2 m/s2
- 10 m/s2
- 30 m/s2
3.2 Representing Acceleration with Equations and Graphs
For the motion of a falling object, which graphs are straight lines?
- Acceleration versus time only
- Displacement versus time only
- Displacement versus time and acceleration versus time
- Velocity versus time and acceleration versus time
A bullet in a gun is accelerated from the firing chamber to the end of the barrel at an average rate of 6.30×105 m/s2 for 8.10×10−4 s. What is the bullet’s final velocity when it leaves the barrel, commonly known as the muzzle velocity?
- 7.79 m/s
- 51.0 m/s
- 510 m/s
- 1020 m/s
Short Answer
3.1 Acceleration
True or False—The vector for a negative acceleration points in the opposite direction when compared to the vector for a positive acceleration.
- True
- False
- -5 m/s
- -1 m/s
- 1 m/s
- 5 m/s
How is the vector arrow representing an acceleration of magnitude 3 m/s2 different from the vector arrow representing a negative acceleration of magnitude 3 m/s2?
- They point in the same direction.
- They are perpendicular, forming a 90° angle between each other.
- They point in opposite directions.
- They are perpendicular, forming a 270° angle between each other.
How long does it take to accelerate from 8.0 m/s to 20.0 m/s at a rate of acceleration of 3.0 m/s2?
- 0.25 s
- 4.0 s
- 9.33 s
- 36 s
3.2 Representing Acceleration with Equations and Graphs
If a plot of displacement versus time is linear, what can be said about the acceleration?
- Acceleration is 0.
- Acceleration is a non-zero constant.
- Acceleration is positive.
- Acceleration is negative.
True or False—The image shows a velocity vs. time graph for a jet car. If you take the slope at any point on the graph, the jet car’s acceleration will be 5.0 m/s2.
- True
- False
When plotted on the blank plots, which answer choice would show the motion of an object that has uniformly accelerated from 2 m/s to 8 m/s in 3 s?
- The plot on the left shows a line from (0,2) to (3,8) while the plot on the right shows a line from (0,2) to (3,2).
- The plot on the left shows a line from (0,2) to (3,8) while the plot on the right shows a line from (0,3) to (3,3).
- The plot on the left shows a line from (0,8) to (3,2) while the plot on the right shows a line from (0,2) to (3,2).
- The plot on the left shows a line from (0,8) to (3,2) while the plot on the right shows a line from (0,3) to (3,3).
When is a plot of velocity versus time a straight line and when is it a curved line?
- It is a straight line when acceleration is changing and is a curved line when acceleration is constant.
- It is a straight line when acceleration is constant and is a curved line when acceleration is changing.
- It is a straight line when velocity is constant and is a curved line when velocity is changing.
- It is a straight line when velocity is changing and is a curved line when velocity is constant.
Extended Response
3.1 Acceleration
- The direction of the initial acceleration vector will point towards the wall and its magnitude will be less than the acceleration vector of the crash.
- The direction of the initial acceleration vector will point away from the wall and its magnitude will be less than the vector of the crash.
- The direction of the initial acceleration vector will point towards the wall and its magnitude will be more than the acceleration vector of the crash.
- The direction of the initial acceleration vector will point away from the wall and its magnitude will be more than the acceleration vector of the crash.
A car accelerates from rest at a stop sign at a rate of 3.0 m/s2 to a speed of 21.0 m/s, and then immediately begins to decelerate to a stop at the next stop sign at a rate of 4.0 m/s2. How long did it take the car to travel from the first stop sign to the second stop sign? Show your work.
- 1.7 seconds
- 5.3 seconds
- 7.0 seconds
- 12 seconds
3.2 Representing Acceleration with Equations and Graphs
True or False—Consider an object moving with constant acceleration. The plot of displacement versus time for such motion is a curved line while the plot of displacement versus time squared is a straight line.
- True
- False
- 0.574 s
- 0.956 s
- 1.53 s
- 1.91 s