Question 69 of 308

Consider a rubber ball freely falling from a height $h=4.9 \mathrm{~m}$ onto a horizontal elastic plate. Assume that the duration of collision is negligible and the collision with the plate is totally elastic. Then the velocity as a function of time the height as function of time will be

A
BCD

Show answer and solution▾

Answer: (C)

$\mathrm{h}=\frac{1}{2} \mathrm{gt}^2, \quad \mathrm{v}=-\mathrm{gt}$ and after the collision, $\mathrm{v}=\mathrm{gt}$.
(parabolic) (straight line)
Collision is perfectly elastic then ball reaches to same height again and again with same velocity.