Equal charges $q$ are placed at the four corners $A,\,B,\,C,\,D$ of a square of length $a$. The magnitude of the force on the charge at $B$ will be

  • A

    $\frac{{3{q^2}}}{{4\pi {\varepsilon _0}{a^2}}}$

  • B

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

  • C

    $\left( {\frac{{1 + 2\sqrt 2 }}{2}} \right)\frac{{{q^2}}}{{4\pi {\varepsilon _0}{a^2}}}$

  • D

    $\left( {2 + \frac{1}{{\sqrt 2 }}} \right)\frac{{{q^2}}}{{4\pi {\varepsilon _0}{a^2}}}$

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