Driving home from school one day, you spot a ball rolling out into the street (see the figure ). You brake for 1.40 , slowing your 950- car from 16.0 to 9.50 .
There is no figure, and your numbers have no dimensions.
There also is no question.
To calculate the average acceleration of the car, you need to use the following formula:
average acceleration = (final velocity - initial velocity) / time
In this case, the initial velocity is 16.0 m/s, the final velocity is 9.50 m/s, and the braking time is 1.40 seconds.
Let's plug in the values to calculate the average acceleration:
average acceleration = (9.50 m/s - 16.0 m/s) / 1.40 s
To simplify the equation, we subtract 9.50 from 16.0 first:
average acceleration = (-6.50 m/s) / 1.40 s
Finally, we divide -6.50 m/s by 1.40 s to get the answer:
average acceleration ≈ -4.64 m/s²
Therefore, the average acceleration of the car during the 1.40-second braking period is approximately -4.64 m/s².