The work done required to increase the separation distance from \[{{\operatorname{x}}_{1}} to {{x}_{1}}+d\]between two masses \[{{\operatorname{m}}_{1}} and {{m}_{2}}\]is

\[\frac{G{{m}_{1}}{{m}_{2}}{{x}_{1}}}{\left( {{x}_{1}}+d \right)d}\]

\[\frac{G{{m}_{1}}{{m}_{2}}d}{{{x}_{1}}\left( {{x}_{1}}+d \right)}\]

\[\frac{-G{{m}_{1}}{{m}_{2}}{{x}_{1}}}{\left( {{x}_{1}}+d \right)}\]

The work done required to increase the separation distance from \[{{\o

1.	The work done required to increase the separation distance from \[{{\operatorname{x}}_{1}} to {{x}_{1}}+d\]between two masses \[{{\operatorname{m}}_{1}} and {{m}_{2}}\]is
A.	\[\frac{G{{m}_{1}}{{m}_{2}}d}{{{x}_{1}}\left( {{x}_{1}}+d \right)}\]
B.	\[\frac{G{{m}_{1}}{{m}_{2}}{{x}_{1}}}{\left( {{x}_{1}}+d \right)d}\]
C.	\[\frac{-G{{m}_{1}}{{m}_{2}}{{x}_{1}}}{\left( {{x}_{1}}+d \right)}\]
D.	none of these
Answer» B. \[\frac{G{{m}_{1}}{{m}_{2}}{{x}_{1}}}{\left( {{x}_{1}}+d \right)d}\]