physics
posted by mike .
You drop a ball from a height of 2.8 m, and it bounces back to a height of 1.0 m. (Ignore air resistance.)
(a) What fraction of its initial energy is lost during the bounce?
b) What is the ball's speed just as it leaves the ground after the bounce?
(c) Where did the energy go?

What is the ratio of the potential energy between h=1.0 and h=2.8 m?
v = sqrt(2*H*g)