A ball is released from the top of a tower of height h metre. It takes T second to reach the ground. What is the position of the ball in `T/3` second?

Options

A. `(h)/(9)` metres from the ground.
B. `(7h)/(9)` metres from the ground
C. `(8h)/(9)` metres from the ground
D. `(17h)/(18)` metres from the ground.

Answer

c

Explanation

Given that the time taken by the ball to reach the ground from a tower of height h, t=T
`h=(1)/(2)gT^(2)`
`(1)/(2)gT^(2)=h`
Let x be the distance covered by the ball from t=0 to t=T/3s
`x=0+(1)/(2)g((T)/(3))^(2)=(1)/(9)((1)/(2)gT^(2))`
`x=(h)/(9)`
height of the point reached by the ball from ground
`h=h-x=h-(h)/(9)=(8h)/(9)`