Two identical particles of mass m carry a charge $Q$ each. Initially one is at rest on a smooth horizontal plane and the other is projected along the plane directly towards first particle from a large distance with speed $v.$ The closest distance of approach be 

  • A

    $\frac{1}{{4\pi {\varepsilon _0}}}\frac{{{Q^2}}}{{m\nu }}$

  • B

    $\frac{1}{{4\pi {\varepsilon _0}}}\frac{{4{Q^2}}}{{m{\nu ^2}}}$

  • C

    $\frac{1}{{4\pi {\varepsilon _0}}}\frac{{2{Q^2}}}{{m{\nu ^2}}}$

  • D

    $\frac{1}{{4\pi {\varepsilon _0}}}\frac{{3{Q^2}}}{{m{\nu ^2}}}$

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  • [KVPY 2011]