Question

A car stopped after travelling distance 8 m due to applying brakes at the speed of 40 m/s. Find acceleration and retardation of car in that period, 

(v² – u² = 2as)

Answer 1

Here u = 40 m/s; v = 0 (vehicle stopped); s = 8 m; a =? 

v² – u² = 2as 

0 – 40² = 2 × a × 8

a = \(\frac{-(40)(40)}{2\,\times \,8}\) = -100m/s

Acceleration = 100 m/s² with retardation on (- sign).