A car is being driven at a speed of 20 ms^-1 when brakes are applied to bring it to rest in 5 s. The deceleration produced in this case will be

u (Initial Velocity) = 20 m/sec

v (final velocity) = 0 m/sec (at rest)

time (t) = 5 seconds

v = u + a.t – (i)

⇒ a =

⇒ a=

a=

a = -4 ms^-2

Therefore Deceleration produced is 4 ms^-2

Note : Since in this question value of deceleration has been asked,

Don’t get confused with the signs, Deceleration= -(Acceleration).