Question

A ring having non-uniform distribution of mass $M$ and radius $R$ is being considered. A point mass $m_0$ is taken slowly towards the ring. In doing so, work done by the external force against gravitational force exerted by ring is

• A. $\frac{GM{m}_0}{\sqrt{2}R}$
• B. $\frac{GM{m}_0}{R}[\frac{1}{\sqrt{2}}-\frac{1}{\sqrt{5}}]$
• C. $\frac{GM{m}_0}{R}[\frac{1}{\sqrt{5}}-\frac{1}{\sqrt{2}}]$
• D. Unpredictable

Answer 1

The correct option is D Unpredictable

It is not possible to calculate the change in potential energy, as the nature of mass distribution is not known