When a constant force is applied to a body moving with constant acceleration, power does not remain constant. For power to be constant, the force has to vary with speed as follows

  • A

    $F \propto \frac{1}{\upsilon }$

  • B

    $F \propto \frac{1}{\sqrt \upsilon }$

  • C

    $F \propto {\upsilon }$

  • D

    $F \propto {\upsilon ^2}$

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