Question

a bus is running at the speed of 18 km/h is stopped in 2.5 sec by applying breaks . calculate the retardation produced.

Answer 1

u = 18 km/h = 18 × 5/18 = 5 m/s
v = 0 m/s
t = 2.5 s

Acceleration= (v-u)/t = -5/2.5 = -2 m/s^2

Retardation is negative of acceleration. Thus retardation is 2 m/s^2

Answer 2

A bus is running at the speed of 18 km/h is stopped in 2.5 sec by applying brakes.

Calculate the retardation produced.

Initial velocity = 18 km/h = 18×5/18 m/sec

= 5 m/sec

[ km/h = 5/18 m/sec ]

final velocity = zero

acceleration = change in velocity/time

= ( final velocity - initial velocity)/time

= ( 0 - 5)/2.5 = -2 m/s²

So, retardation = 2m/s²