Four equal charges $Q$ are placed at the four corners of a square of each side is $'a'$. Work done in removing a charge $-Q$ from its centre to infinity is

  • [AIIMS 1995]
  • A

    $0$

  • B

    $\frac{{\sqrt 2 {Q^2}}}{{4\pi {\varepsilon _0}a}}$

  • C

    $\frac{{\sqrt 2 {Q^2}}}{{\pi {\varepsilon _0}a}}$

  • D

    $\frac{{{Q^2}}}{{2\pi {\varepsilon _0}a}}$

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