Work done in time $t $ on a body of mass $m$ which is accelerated from rest to a speed $v$ in time ${t_1}$ as a function of time $t$ is given by

  • A

    $\frac{1}{2}m\frac{v}{{{t_1}}}{t^2}$

  • B

    $m\frac{v}{{{t_1}}}{t^2}$

  • C

    $\frac{1}{2}{\left( {\frac{{m\,v}}{{{t_1}}}} \right)^2}{t^2}$

  • D

    $\frac{1}{2}m\frac{{{v^2}}}{{t_1^2}}{t^2}$

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