Question

(1) A car weighing 2000kg travelling at 20m/s stops at a distance of 40m decelerating
uniformly. What is the force exerted on it by brakes ? What is the work done by the brakes?​

Answer 1

Answer:

f=ma

f=2000×v-u/2s

f=2000×0-20/2×40

by cancelling 2 and 2000

f=1000×-1/2

by cancelling 2and 1000

f=-500