The diagram shows a small bead of mass $m$ carrying charge $q$. The bead can freely move on the smooth fixed ring placed on a smooth horizontal plane. In the same plane a charge $+Q$ has also been fixed as shown. The potential atthe point $P$ due to $+Q$ is $V$. The velocity with which the bead should projected from the point $P$ so that it can complete a circle should be greater than

115-883

  • A

    $\sqrt {\frac{{6qV}}{m}} $

  • B

    $\sqrt {\frac{{qV}}{m}} $

  • C

    $\sqrt {\frac{{3qV}}{m}} $

  • D

    none

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