A block of weight $W$ is kept on a rough horizontal surface (friction coefficient $\mu$). Two forces $W/2$ each are applied as shown in the figure. Choose the $CORRECT$ statement :-

822-651

  • A

    for $\mu > \frac{\sqrt 3}{5}$ block will move

  • B

    for $\mu > \frac{\sqrt 3}{5}$, work done by friction force is zero (in ground frame).

  • C

    $\mu > \frac{\sqrt 3}{5}$ friction force will do positive work (in ground frame)

  • D

    for $\mu > \frac{\sqrt 3}{5}$ block will move

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