To find the overall average acceleration, we need to consider the total change in velocity and the total time.
First, let's find the total change in velocity:
Change in velocity = final velocity - initial velocity
For part (a), the initial velocity was 0 ft/s and the final velocity was 34 ft/s. So, the change in velocity for part (a) is 34 ft/s - 0 ft/s = 34 ft/s.
For part (b), the initial velocity was 34 ft/s and the final velocity was 68 ft/s. So, the change in velocity for part (b) is 68 ft/s - 34 ft/s = 34 ft/s.
For part (c), the initial velocity was 68 ft/s and the final velocity was 51 ft/s. So, the change in velocity for part (c) is 51 ft/s - 68 ft/s = -17 ft/s (negative because the car is slowing down).
Now, let's find the total time:
Total time = time for part (a) + time for part (b) + time for part (c)
Total time = 5.5 s + 4.5 s + 3.5 s = 13.5 s
Finally, let's calculate the overall average acceleration:
Overall average acceleration = (total change in velocity) / (total time)
Overall average acceleration = (34 ft/s + 34 ft/s - 17 ft/s) / 13.5 s
Overall average acceleration = 51 ft/s / 13.5 s
Overall average acceleration ≈ 3.78 ft/s²
Therefore, the overall average acceleration for the total time is approximately 3.78 ft/s².
A car travels on a straight, level road.
(a) Starting from rest, the car is going 34 ft/s (23 mi/h) at the end of 5.5 s. What is the car's average acceleration in ft/s2?
magnitude
Correct: Your answer is correct.
ft/s2
direction
Correct: Your answer is correct.
(b) In 4.5 more seconds, the car is going 68 ft/s (46 mi/h). What is the car's average acceleration for this time period?
magnitude
Correct: Your answer is correct.
ft/s2
direction
Correct: Your answer is correct.
(c) The car then slows to 51 ft/s (35 mi/h) in 3.5 s. What is the average acceleration for this time period?
magnitude
Correct: Your answer is correct.
ft/s2
direction
Correct: Your answer is correct.
(d) What is the overall average acceleration for the total time?
1 answer