A car accelerates at a constant rate from zero to 36.8 m/s in 10 seconds and then slows to 13.9 m/s in 5 seconds. What is its average acceleration to the nearest tenth of a m/s2 during the 15 seconds?
What was the acceleration during the first 10 seconds in the previous problem?
To find the average acceleration during the 15 seconds, we need to calculate the change in velocity and divide it by the time taken.
1. First, we calculate the change in velocity during the first 10 seconds:
Change in velocity = final velocity - initial velocity
Change in velocity = 36.8 m/s - 0 m/s
Change in velocity = 36.8 m/s
2. Next, we calculate the change in velocity during the last 5 seconds:
Change in velocity = final velocity - initial velocity
Change in velocity = 13.9 m/s - 36.8 m/s
Change in velocity = -22.9 m/s (negative because it is slowing down)
3. Now, we calculate the average acceleration for the entire 15 seconds:
Average acceleration = change in velocity / time taken
Average acceleration = (36.8 m/s - 22.9 m/s) / 15 s
Average acceleration = 13.9 m/s / 15 s
Average acceleration = 0.9267 m/s² (rounded to the nearest tenth)
Therefore, the average acceleration to the nearest tenth of a m/s² during the 15 seconds is approximately 0.9 m/s².