A particle of mass `10 g` is kept on the surface of a uniform sphere of mass `100 kg` and radius `10 cm`. Find the work done against the gravitational force between them to take the particle far away from the sphere.

Options

A. `13.34xx10^(-10)J`
B. `3.33xx10^(-10)J`
C. `6.67xx10^(-9)J`
D. `6.67xx10^(-10)J`

Answer

D

Explanation

Work done `=U_(f)-U_(i)=U_(f)=0-(-0)`
`U_(i)=(GM_(1)m_(2))/(R)=(6.67xx10^(-4)xx100xx10xx10^(-1))/(10xx10^(2))`
`=(6.67xx10^(-11)xx100xx10xx10^(-3))/(10xx10^(-2))=6.67xx10^(-10)`