Question

A car travels with a uniform velocity of 25 m/ s for 5 s . the brakes are then applied and the car is uniformly retarded and comes to rest in further 10s . Draw A Velocity Time Graph And Use It To Find (i) the distance which the car travel After the brakes are applied.(ii) the retardation​

Answer 1

Retardation is obtained using the formula "v = u - a×t " , where v is final speed which is zero in this case,

u is initial speed , a is retardation and t is time

(1) retardation a = u/t = 25/10 = 2.5 m/s2 .

(2) distance travelled before applying break = 25×5 = 125 m

(3) distance S travelled after applying break is given by, S = u×t - (1/2)×a×t2 = 25×10 - (1/2)×2.5×100 = 125 m