JEE Main & Advanced Physics Gravitation / गुरुत्वाकर्षण Question Bank Gravitation Potential

  • question_answer
    \[{{v}_{e}}\] and \[{{v}_{p}}\] denotes the escape velocity from the earth and another planet having twice the radius and the same mean density as the earth. Then [NCERT 1974; MP PMT 1994]

    A)             \[{{v}_{e}}={{v}_{p}}\]

    B)               \[{{v}_{e}}={{v}_{p}}/2\]

    C)             \[{{v}_{e}}=2{{v}_{p}}\]

    D)               \[{{v}_{e}}={{v}_{p}}/4\]

    Correct Answer: B

    Solution :

        \[{{v}_{e}}=\sqrt{\frac{2GM}{R}}=R\sqrt{\frac{8}{3}\pi G\rho }\] If mean density is constant then \[{{v}_{e}}\propto R\] \[\frac{{{v}_{e}}}{{{v}_{p}}}=\frac{{{R}_{e}}}{{{R}_{p}}}=\frac{1}{2}\]Þ\[{{v}_{e}}=\frac{{{v}_{p}}}{\text{2}}\]


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