JEE Main & Advanced Physics Gravitation / गुरुत्वाकर्षण Question Bank Kepler's Laws of Planetary Motion

  • question_answer
    The mass of a planet that has a moon whose time period and orbital radius are T and R respectively can be written as                                 [AMU 1995]

    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)               \[16{{\pi }^{2}}{{R}^{3}}{{G}^{-1}}{{T}^{-2}}\]

    Correct Answer: A

    Solution :

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


You need to login to perform this action.
You will be redirected in 3 sec spinner