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MHT CET2018PhysicsRotational Motion

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 the disc with angular velocity ω in time t ?

Options

  1. AM R ω 4 t
  2. BM R ω 2 t
  3. CM R ω t
  4. DM R ω t

Correct answer

B. M R ω 2 t

Step-by-step solution

τ = I α F × R = M R 2 2 × ω t F = M R 2 × ω t

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