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MHT CET20225 Aug 2022Evening ShiftPhysicsRotational MotionActual

A disc has mass ' m ' and radius ' R '. How much tangential force should be applied to the rim of the disc so as to rotate with angular velocity ' ' in time t?

Options

  1. AmR 2 t
  2. BmR t
  3. CmR 4 t
  4. DmR t

Correct answer

A. mR 2 t

Step-by-step solution

Angular acceleration, = t And, moment of inertia of disc I = 1 2 MR ^2 Hence, torque, aligned & =I = 1 2 M^2 t c & =F R & F= R & F= M R 2 t aligned

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