Question

A ball is dropped vertically from a height d above the ground. It hits the ground and bounces up vertically to a height $\frac { d } { 2 }$ . Neglecting subsequent motion and air resistance, its velocity $v$ varies with the height h above the ground as.

• A.
• B.
• C.
• D.

Answer 1

Answer: (A)

Answer 2

When ball is dropped from height d its velocity will be zero. As ball comes downward h decreases and $v$ increases just before the rebound from the earth

h = 0 and v = maximum and just after rebound velocity reduces to half and direction becomes opposite.

As soon as the height increases its velocity decreases and becomes zero at $h = \frac { d } { 2 }$ .

This interpretation is clearly shown by graph (1).