Someone is using a scissors to cut a wire of circular cross section and negligible weight. The wire slides in the direction away from the hinge until the angle between the scissors blades becomes $2 \alpha$. The friction coefficient between the blades and the wire, is :-

822-566

  • A

    $\sqrt {1-tan \alpha}$

  • B

    $2cos \alpha$

  • C

    $tan \alpha$

  • D

    $2\, tan \alpha$

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