Concept explainers
Starting from rest, a car accelerates at a constant rate of 4.0 m/s2 for a time of 5 seconds.
- a. Compute the velocity of the car at 1 s, 2 s, 3 s, 4 s, and 5 s and plot these velocity values against time.
- b. Compute the distance traveled by the car for these same times and plot the distance values against time.
(a)
The velocity of the car after each second.
Answer to Problem 18E
The velocities after 1s, 2s, 3s, 4s and 5s are 4 m/s, 8 m/s, 12 m/s, 16 m/s and 20 m/s respectively.
Explanation of Solution
Given info: Acceleration is
Write the formula for average acceleration.
Here,
a is the average acceleration
t is the time
Re-arrange the above equation to get
For
Substitute 0 m/s for
For
Substitute 0 m/s for
For
Substitute 0 m/s for
For
Substitute 0 m/s for
For
Substitute 0 m/s for
The velocity time graph is given below.
Conclusion:
The velocities after 1s, 2s, 3s, 4s and 5s are 4 m/s, 8 m/s, 12 m/s, 16 m/s and 20 m/s respectively.
(b)
The distance travelled after each second.
Answer to Problem 18E
The distances after 1s, 2s, 3s, 4s and 5s are 2 m, 8 m, 18 m, 32 m and 50 m respectively.
Explanation of Solution
Given info: Acceleration is
Write the formula to calculate the distance.
Here,
d is the distance
For
Substitute 0 m/s for
For
Substitute 0 m/s for
For
Substitute 0 m/s for
For
Substitute 0 m/s for
For
Substitute 0 m/s for
The distance time graph is,
Conclusion:
The distances after 1s, 2s, 3s, 4s and 5s are 2 m, 8 m, 18 m, 32 m and 50 m respectively.
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Chapter 2 Solutions
Physics of Everyday Phenomena
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