Initial velocity, u=50ms−1
At maximum height final velocity, v=0
Apply first kinematic equation of motion
v=u+at
0=50−10t
t=5sec
Apply second kinematic equation of motion
v2−u2=2as
02−502=2(−10)h
h=125m
Hence, at maximum height final velocity is zero, time taken 5secand maximum height is 125m