A particle of mass $m$ at rest is acted upon by a force $P$ for a time $t.$ Its kinetic energy after an interval $t$ is

  • A

    $\frac{{{P^2}{t^2}}}{m}$

  • B

    $\frac{{{P^2}{t^2}}}{2m}$

  • C

    $\frac{{{P^2}{t^2}}}{3m}$

  • D

    $\frac{{{P}{t}}}{2m}$

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