Question

a body is thrown from a tower of height 45m another body is thrown up at the same instant with speed u from a height of 30m if they reach the ground simultaneously , u is(g=10m/s^2)

Answer 1

the ans=5m/s

Answer 2

For the first body
45=1/2*10*t^2
45=5t^2
t^2=9
t=3
For the second body
-30=3u-1/2*10*9
-30=3u-45
45-30=3u
15=3u
u=5m/s