u =10m/s,v =0, t =20s
so we can find a = v-u / t , a = 0 - 10/20, = -0.5.
That will be the retardation. Regards.
When a car driver travelling at a speed of 10 ms applies brakes and brings the car to rest in 20s, then retardation will be :
(a) + 2 m/s2 (b) −2m/s2 (c) −0.5m/s2 (d) +0.5m/s2