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MHT CET202120 Sep 2021Evening ShiftPhysicsRotational MotionActual

A disc of radius 0.4 ~m and mass 1 ~kg rotates about an axis passing through its center and perpendicular to its plane. The angular acceleration of the disc is 10 rad / s ^2 . The tangential force applied to the rim of the disc is

Options

  1. A4 ~N
  2. B1 ~N
  3. C2 ~N
  4. D8 ~N

Correct answer

C. 2 ~N

Step-by-step solution

R =0.4 ~m , M =1 ~kg , =10 rad / s ^2 Moment of inertia, I = MR ^2 2 = 1 (0.4)^2 2 =0.08 ~kg ~m ^2 Torque, = RF = I F = I R = 0.08 10 0.4 =2 ~N

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