Question

The initial velocity of a train which is stopped
in 20 s by applying brakes (retardation due to
brakes being 1.5 m s-?) is​

Answer 1

Answer:

30 m/s

Explanation:

initial velocity, u = ?

final velocity, v = 0 m/s

Retardation, a = -1.5 m/s

Time, t = 20 s

Acc to Que,

(v-u)/t = a

(0 - u)/20 = -15/10

-u = -3*20/2

-u = -30 m/s

Therefore, initial velocity, u = 30 m/s