A particle of mass $10 \mathrm{~g}$ is kept on the surface of a uniform sphere of mass $100 \mathrm{~kg}$…

A particle of mass $10 \mathrm{~g}$ is kept on the surface of a uniform sphere of mass $100 \mathrm{~kg}$ and radius $10 \mathrm{~cm}$. Find the work to be done against the gravitational force between them to take the particle far away from the sphere (you may take $\mathrm{G}=6.67 \times 10^{-11} \mathrm{Nm}^2 / \mathrm{kg}^2$ )
  1. $13.34 \times 10^{-10} \mathrm{~J}$
  2. $3.33 \times 10^{-10} \mathrm{~J}$
  3. $6.67 \times 10^{-9} \mathrm{~J}$
  4. $6.67 \times 10^{-10} \mathrm{~J}$

Solution

$\mathrm{w}=\mathrm{GMm} / \mathrm{R}=6.67 \times 10^{-10} \mathrm{~J}$

Asked in: JEE Main 2005

Practice more Gravitation questions on Aicharya