Two charges $+q$ and $-3q$ are placed on $x-$ axis separated by a distance $d$. ($-3q$ is right of $q$) Where should a third charge $2q$ be placed such that it will not experience any force ?

  • A

    $\frac{d}{2}\,\left( {1 + \sqrt 3 } \right)$ to the left of $q$

  • B

    $\frac{d}{2}\,\left( {1 - \sqrt 3 } \right)$ to the left of $q$

  • C

    $\frac{d}{2}\,\left( {1 - \sqrt 3 } \right)$ to the right of $q$

  • D

    $\frac{d}{2}\,\left( {1 + \sqrt 3 } \right)$ to the right of $q$

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