Question

A moving train is brought to rest within 20 seconds by applying brakes. find the initial velocity, if the retardation due to brakes is 2m/s square

Answer 1

V=0M/S
T=20 S
A=-2M/S^2
U=?
A=V-U/T
-2=0-V/20
-40=-V
V=40 M/S

Answer 2

v--0m is the answer i think