A disc rotates about its axis of symmetry in a hoizontal plane at a steady rate of $3.5$ revolutions per second. A coin placed at a distance of $1.25\,cm$ from the axis of rotation remains at rest on the disc. The coefficient of friction between the coin and the disc is $(g\, = 10\,m/s^2)$

  • [JEE MAIN 2018]
  • A

    $0.5$

  • B

    $0.7$

  • C

    $0.3$

  • D

    $0.6$

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