Amplified Rebound Height Two small rubber balls are dropped from rest at a height $h$ above a hard floor. When the balls are released, the lighter ball (with mass $m$ ) is directly above the heavier ball (with mass $M$ ). Assume the heavier ball reaches the floor first and bounces elastically; thus, when the balls collide, the ball of mass $M$ is moving upward with a speed $v$ and the ball of mass $m$ is moving downward with essentially the same speed. In terms of $h,$ find the height to which the ball of mass $m$ rises after the collision. (Use the results given in Problem $88,$ and assume the balls collide at ground level.)