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
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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