Question

A Car is moving in a straight line with speed 54km/h. It is stopped in 8s by applying the brakes.

(1) Find is the speed of Car in m/s

(2) retardation

(3) the speed of the car after 3 seconds of applying the brakes​

Answer 1

Explanation:

1.speed of car in m/s=54×(1000/36000)or

=54×(5/18) ≈ 15m/s

2.retardation:- v=u+at

v=0,u=15m/s,t=8s

a= -15/8m/s²

3. v= 15+(-15/8)×3

v= 15-45/8

v= 9.3m/s