Posted by Pankaj kumar suman on Sunday, December 23, 2012 at 10:05am.
A boy standing on top a building with a height of 500m throws a ball vertically upwards. The balls take 40s to reach to the ground. Neglecting the height of the boy throwing the ball, determine the velocity of the ball.

science  Anonymous, Tuesday, December 25, 2012 at 4:49pm
0 = .5 g (40^2) + Vo(40) + 500
solve for Vo (the throwing velocity)
Vo / g is the time to max height
40  (Vo / g) is the free fall time
(40 * g)  Vo is the impact velocity