Question

A train is moving with a velocity of 90km/h. When the driver applies brakes the train comes to halt in 10seconds.
(a)Calculate the retardation
(b)Distance covered by the train in 10seconds.

Answer 1

u=90km/h = 90×5/18 = 25m/sec
v= 0m/s
a = -0.5m/s²
then using first equation of motion ,
v=u+at
0 = 25+(-0.5)t
0=25-0.5t
0.5t=25
t= 25/0.5 = 50 seconds