Two identical non-conducting thin hemispherical shells each of radius $R$ are  brought in contact to make a complete sphere . If a total charge $Q$ is uniformly distributed on them, how much minimum force $F$ will  be required to hold them together

  • A

    $F = \frac{{{Q^2}}}{{16\pi {\varepsilon _0}{R^2}}}$

  • B

    $F = \frac{{{Q^2}}}{{32\pi {\varepsilon _0}{R^2}}}$

  • C

    $F = \frac{{{Q^2}}}{{64\pi {\varepsilon _0}{R^2}}}$

  • D

     $\frac{{{Q^2}}}{{32\pi {\varepsilon _0}{R^2}}} >F> \frac{{{Q^2}}}{{64\pi {\varepsilon _0}{R^2}}}$

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