Question

A car travelling at a velocity of 54 kilometre per hour is brought to rest in 5 seconds by applying brakes. What is the acceleration of the CAR? ​

Answer 1

Answer:

-3m/s^2

Explanation:

i hope u understand

Answer 2

Answer:

3 m/s²

Explanation:

The initial velocity is given, 54km/hr = 54 ∗ 5/18 = 15 m/s

Final velocity is 0 m/s , the body comes to rest.

So, the change in velocity, Δv = 15m/s

Thus we need to change the velocity by 15m/s in Δt = 5 seconds . The retardation, assuming it is uniform, is the velocity change per second .Thus, the retardation is Δv/Δt = 15/5 = 3m/s²