Question

A hall is thrown vertically upwards
with a velocity of 20ms from the top
of a a multi-storied building. The height of
a point from where the ball is thrown
is asm. How high will the wall rise? How
long will it take?​

Answer 1

Answer:

t=5s

Explanation:

Time to reach maximum height can be obtained from v=u+at

0=20+(−10)t

t=2s

s=ut+0.5at² =20(2)+0.5(−10)(2)²  =20m

Thus, total distance for maximum height is 45 m

s=ut+0.5at²

45=0+0.5(10)(t')²

t'=3s

Total time= 3+2= 5s