Question

acceleration. Examples of these concepts are discussed. Sample calculations of
acceleration and graphs representing accelerated motion are presented.
Reading Strategy (page 342)
Summarizing Read the section on acceleration. Then complete the
concept map to organize what you know about acceleration. For more
information on this Reading Strategy, see the Reading and Study Skills
in the Skills and Reference Handbook at the end of your textbook.
What Is Acceleration? (pages 342–345)
1. The rate at which velocity changes is called
.
2. In terms of speed and direction, in what ways can an object
accelerate?
3. Because acceleration is a quantity that has both magnitude and
direction, it is a(n)
.
4. Is the following sentence true or false? Acceleration is the result of
increases or decreases in speed.
5. Ignoring air resistance, a rock in free fall will have a velocity of
after 4.0 seconds.
6. A horse on a carousel that is moving at a constant speed is
accelerating because
.
7. Describe constant acceleration.
Calculating Acceleration (pages 345–346)
8. Write the equation used to calculate the acceleration of an object.
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Physical Science Guided Reading and Study Workbook
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Chapter 11
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Acceleration
is a change
in
is measured
in units of

9. Is the following sentence true or false? When the final velocity is
less than the initial velocity of an object, the acceleration is
negative.
10. A skateboarder begins down a ramp at a speed of 1.0 m/s. After
3 seconds, her speed has increased to 4.0 m/s. Calculate
her acceleration.
a. 1.0 m/s2
b. 3.0 m/s2
c. 5.0 m/s2
d. 9.8 m/s2
Graphs of Accelerated Motion (pages 346–348)
11. A speed-time graph in which the displayed data forms a straight
line is an example of a(n)
.
For questions 12 through 15, refer to the graphs below.
12. Graph A represents the motion of a downhill skier. How fast was the skier moving
after traveling down the hill for 2.5 seconds?
13. In which graph does an object move at constant speed during the
first 4 seconds?
14. Graph B represents the motion of a mountain biker. What is the biker’s
speed at times of 10 s and 20 s?
15. Determine the acceleration of the mountain biker during the
10 second to 20 second time period. Show your work.
16. The plotted data points representing acceleration in a distance-time
graph form a(n)
.
Instantaneous Acceleration (page 348)
17. The measure of how fast a velocity is changing at a specific instant
is known as
.
Name ___________________________
Class ___________________
Date _____________
Chapter 11
Motion
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Physical Science Guided Reading and Study Workbook
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Chapter 11
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16
12
4
0
Speed (m/s)
Time (s)
0
1
2
3
4
Acceleration Graph A
2
5
6
7
4
3
1
0
Speed (m/s)
Time (s)
0
5
10
15
20

Answer 1

1. Acceleration.

2. By speeding up, slowing down (decelerating), or changing direction.

3. A vector.

4. False — acceleration can also be a change in direction without a speed change.

5. v = g t ≈ 9.8 m/s^2 × 4.0 s = 39.2 m/s downward (≈ 39 m/s downward).

6. Because its direction is continuously changing (centripetal acceleration toward the center).

7. Constant acceleration means the velocity changes by equal amounts in equal time intervals (the acceleration value is the same at all times).

8. a = (vf − vi) / t.
Acceleration is a change in velocity and is measured in meters per second squared (m/s^2).

9. True (with a consistent sign convention).

10. a = (4.0 − 1.0) / 3.0 = 1.0 m/s^2. (Answer a)

11. Constant acceleration (a straight line on a speed‑time graph indicates constant acceleration).

12. 5.0 m/s (graph A increases linearly from 0 m/s at 0 s to 8 m/s at 4 s → slope 2 m/s² → v(2.5) = 2 × 2.5 = 5 m/s).

13. Graph B.

14. From Graph B: at 10 s the speed is 3 m/s; at 20 s the speed is 6 m/s.

15. a = (vf − vi) / Δt = (6 − 3) m/s / 10 s = 0.3 m/s^2.

16. A curve (for constant acceleration the distance‑time graph is a parabola).

17. Instantaneous acceleration.