Vertical displacement, h=16m
v2−u2=2ah
0−u2=2(−g)h
u=√2gh=√2×10×16=8√5ms−1
Half of this velocity is 4√5ms−1
v2−u2=2as
(4√5)2−(8√5)2=2(−g)H
H=12m
Hence, at 12 m velocity of ball is half of initial velocity
A ball is thrown vertically upwards attains a maximum height of 45m. What is the time after which velocity of the ball become equal to half the velocity of projection?