A point charge is surrounded symmetrically by six identical charges at distance $r$ as shown in the  figure. How much work is done by the forces of electrostatic repulsion when the point charge $q$ at the centre is removed at infinity 

818-724

  • A

    zero

  • B

    $6{q^{2\,}}\,/\,4\pi {\varepsilon _0}r$

  • C

    ${q^{2\,}}\,/\,4\pi {\varepsilon _0}r$

  • D

    $12{q^{2\,}}\,/\,4\pi {\varepsilon _0}r$

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