The mass of a planet that has a moon whose

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The mass of a planet that has a moon whose time period and orbital radius are $T$ and $R$ respectively can be written as

A

$4{\pi ^2}{R^3}{G^{ - 1}}{T^{ - 2}}$

B

$8{\pi ^2}{R^3}{G^{ - 1}}{T^{ - 2}}$

C

$12{\pi ^2}{R^3}{G^{ - 1}}{T^{ - 2}}$

D

$16{\pi ^2}{R^3}{G^{ - 1}}{T^{ - 2}}$

The mass of a planet that has a moon whose time period and orbital radius are $T$ and $R$ respectively can be written as

$m{\omega ^2}R = \frac{{GMm}}{{{R^2}}}\, \Rightarrow \,{\left( {\frac{{2\pi }}{T}} \right)^2}R = \frac{{GM}}{{{R^2}}}$$ \Rightarrow \,M = \frac{{4{\pi ^2}{R^3}}}{{G{T^2}}}$