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NEST2023PhysicsRotational Motion

A heavy disc of radius R and mass M is placed horizontally. A small coin of mass m placed at a radial distance R / 2 from the centre. The disc is now (t=0) given a constant angular acceleration of magnitude rad s ⁻² about a vertical axis passing through its centre. If _s and _d are the coefficients of static and dynamic friction, respectively, between the coin and the rotating disc, then

Options

  1. Aat t 0 , the force due to static friction acts radially inwards.
  2. Bat t 0 , the magnitude of force due to static friction is always F_s= _s mg .
  3. Cthe coin starts sliding at time t= 1 2 _s g R .
  4. Dthe coin reaches the edge of the disc at time t= 2 ( _d- _s ) g R .

Correct answer

C. the coin starts sliding at time t= 1 2 _s g R .

Step-by-step solution

No solution available.

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