Question

find initial velocity of a train which stopped in 15 sec the retardation is 1.5m/s2

Answer 1

retardation is 1.5 that means acceleration is -1.5
the train stops so final velocity =0
t=15
a=v-u/t
-1.5=0-u/15
u=22.5 m/s

Answer 2

Hi.

Here is your answer------

Given---
Initial velocity(u) =u m/s.
A train is stooped after sometime, thus, Final velocity(v) =0.
Retardation= 1.5 m/s^2.
Time(t) = 15 seconds.

Using formula of retardation,
    Retardation = (u - v)/t
               1.5    =  (u - 0)15
                22.5 = u - 0
        Thus, u = 22.5 m/s    Answer.

Hope it will help u.

Have a nice day.

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