Question

A ball is thrown vertically upward from the point A. A person standing at the height H on the roof of a building tries tobcatch it. He misses the catch the ball overshoots and simultaneously the person starts a stopwatch the ball reaches its highest point and manages to catch it upon its return. By this time the time of interval of T has elapsed as recorded by the stop watch. If g is the acceleration find the velocity at point A at starting

Answer 1

Answer:

$\frac{gT}{2}$

Explanation:

let the velocity of ball be 'u' at the point where the person is standing

We know that the ball returns to the person in time T

$s = ut + \frac{at^{2} }{2}$

If the ball returns to the same point the displacement is 0

⇒ $0 = uT - \frac{gT^{2} }{2}$

⇒u = $\frac{gT}{2}$