acceleration. linear motion. i'm stuck!!!

[Run Haridan]

1. The problem statement, all variables and given/known data
a train moves at a velocity of 60 m s-1 and stops after a distance of 600m. what is its deceleration?


2. Relevant equations
v=s/t



3. The attempt at a solution
this is my working:
u= 0 m s-1
v= 60 m s-1
s= 600 m

v=s/t
60=600/t
t=10 s

...and i'm stuck here. please help!!!

[rl.bhat]

The velocity is not uniform. So you can't use v = s/t. And here initial velocity is 60 m/s and final velocity is 0. Use appropriate kinamatic formula which relates initial velocity, final velocity , acceleration and displacement.

[Run Haridan]

what formula? tell me and i'll try to work it out!

[rl.bhat]

v^2 - u^2 = 2as

[harvellt]

My favorite for finding acceleration is a(\Deltax)=(1/2)(\DeltaV2)