An elevator without a ceiling is ascending up with an acceleration of `5 ms^-2.` A boy on the elevator shoots a ball in vertical upward direction from a height of 2 m above the floor of elevator. At this instant the elevator is moving up with a velocity of `10 ms^-1` and floor of the elevator is at a height of 50 m from the ground. The initial speed of the ball is `15 ms^-1` with respect to the elevator. Consider the duration for which the ball strikes the floor of elevator in answering following questions. (`g=10 ms^-2`)
3. Displacement of ball with respect to ground during its night would be

Options

A. 16.25 m
B. 8.76 m
C. 20.24 m
D. 30.56 m

Answer

D

Explanation

`S=25xx2/13-5xx(2.13)^2`
`=30.56m`