Question

A body is dropped from a height $h$. When loss in its potential energy is $U$ then its velocity is $v$. The mass of the body is:

• A. $\frac{U^2}{2v}$
• B. $\frac{2v}{U}$
• C. $\frac{2v}{U^2}$
• D. $\frac{2U}{v^2}$

Answer 1

The correct option is D $\frac{2U}{v^2}$

loss in PE=gain in KE

$U=\frac{1}{2}m{v}^2$

$m=\frac{2U}{v^2}$