A block of mass $m$ containing a net negative charge $-q$ is placed on a frictionless  horizontal table and is connected to a wall through an unstretched spring of spring  constant $k$ as shown. If horizontal electric field $E$ parallel to the spring is switched on,  then the maximum compression of the spring is :-

816-833

  • A

    $ \sqrt {qE / k}$

  • B

    $ \sqrt {k / qE}$

  • C

    $qE/k$

  • D

    $\frac{2qE}{k}$

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