Question

A ball is thrown up vertically returns to the thrower after 123sec find. a)velocity with which it was thrown up. b)the maximum height it reaches. c)its position after 4sec.

Answer 1

From t=2u/g
123=2u/10
therefore u=615m/s

Now, h= u×u /2g
h=18911.25 m= 18.9 km
from
s =ut +1/2 at*t
s=2380m