Question

A car is moving with a speed of on 108km/h. Brakes are applied to bring the speed of the car to 20m/s when is travelsa distance of 50m. Find the retardation and how long the brakes were applied?

Answer 1

Answer: retardation is 5m/sec2

Time = 2 seconds

Explanation:

Initial velocity, u = 108km/hr = 30 m/sec

Final velocity, v = 20m /sec

Distance,s = 50m

Retardation= a

v2=u2- 2as

400 =900 - 100 a

a = 5m/sec2