A charged particle $q$ is shot towards another charged particle $Q$ which is fixed, with a speed $v$. It approaches $Q$ upto a closest distance $r$ and then returns. If $q$ were given a speed $2v$, the closest distances of approach would be

115-40

  • [AIEEE 2004]
  • A

    $r$

  • B

    $2r$

  • C

    ${{r}/{2}}$

  • D

    ${{r}/{4}}$

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