JEE Main & Advanced JEE Main Paper (Held On 11-Jan-2019 Evening)

  • question_answer
    The mass and the diameter of a planet are three times the respective values for the Earth. The period of oscillation of a simple pendulum on the Earth is 2 s. The period of oscillation of the same pendulum on the planet would be [JEE  Main Online Paper (Held on 11-jan-2019 Evening)]

    A) \[2\sqrt{3}s\]                             

    B) \[\frac{3}{2}s\]

    C) \[\frac{2}{\sqrt{3}}s\]                            

    D)   \[\frac{\sqrt{3}}{2}s\]

    Correct Answer: A

    Solution :

    Time period of a simple pendulum, \[T=2\pi \sqrt{\frac{l}{g}}\] \[{{g}_{p}}=\frac{G{{M}_{p}}}{R_{p}^{2}}=4\frac{G{{M}_{p}}}{D_{p}^{2}}=\frac{(4G{{M}_{E}})}{D_{E}^{2}}\times \frac{3}{{{3}^{2}}}\] \[\left( \because {{g}_{e}}=\frac{4G{{M}_{E}}}{D_{E}^{2}} \right)\] \[{{g}_{p}}=\frac{{{g}_{e}}}{3}\] \[\therefore \]\[\frac{{{T}_{e}}}{{{T}_{p}}}=\sqrt{\frac{{{g}_{p}}}{{{g}_{e}}}}=\frac{1}{\sqrt{3}},{{T}_{p}}=2\sqrt{3}s\]            \[({{T}_{e}}=2s)\]


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