Question

A body released from the top of a tower of height h takes T second to reach the ground. The position of the body at (T/4) second is:

• A. at $\frac{h}{16}$ from the ground
• B. at $\frac{3h}{4}$above the ground
• C. at $\frac{15h}{16}$from the ground
• D. at $\frac{3h}{16}$ below the top of the tower

Answer 1

The correct option is C at $\frac{15h}{16}$from the ground

$h=uT-\frac{1}{2}g{T}^2$
$h=\frac{1}{2}g{T}^2$

At $\frac{T}{4}s$ body has travelled.
$h_1=\frac{1}{2}g(\frac{T}{4}{)}^2=\frac{g}{2}(\frac{T^2}{16})$

So, its distance from ground,
$h_1-4=\frac{g}{2}(T^2-\frac{T^2}{16})=\frac{g}{2}{T}^2\times \frac{15}{16}$$=\frac{15}{16}h$