Question

a car is moving with velocity of 72km/h and it take 5 sec to stop after breaks are applied. calculate the force exerted by brakes on the car if its mass along with the passenger is 900kg.

Answer 1

First find acceleration

a=v-u/t
a=0-20/5
a=-20/5
a=-4m/s2

now

f=m×a
f=900×-4
f=-3600N

Hence force is -3600N

- represent negative force

that's qll