Question

When two different stones of masses $8kg$ and $16kg$ are taken to the same height, then ratio of their potential energies respectively is.

• A. $1:3$
• B. $1:1.5$
• C. $1:1$
• D. $1:2$

Answer 1

The correct option is D $1:2$

Potential energy, $P.E=m\times g\times h$
where $m$ is the mass, $g$ is the acceleration due to gravity and $h$ is the height above the ground to which the object is raised. Potential energy is directly proportional to the mass of the object.
$P.E_1=m_1\times g\times h_1$
$P.E_2=m_2\times g\times h_2$
$\frac{P.E_1}{P.E_2}=\frac{m_{1}g{h}_1}{m_{2}g{H}_2}$
By substituting values,
$\frac{P.E_1}{P.E_2}=\frac{1}{2}$