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` sccond?

Options

A. h/9 metre from the ground
B. 7h/9 metre from the ground
C. 8h/9 metre from the ground
D. 17h/18 metre from the ground.

Answer

C

Explanation

Equation of motion : s =ut `+(1)/(2) "gt"^(2)`
`:. h=0+(1)/(2)gT^(2) or 2h=gT^(2)`
After `T//3s, s=0+(1)/(2)xxg((T)/(3))^(2)=(gT^(2))/(18)`
or `18 s - gT^(2)`
From (i) and (ii) 18 s =2h
or m from top.
`:.` Height from ground `- h - (h)/(9)=(8h)/(9)` m .