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Two masses are attached to a rod end to end. If torque is applied they rotate with angular acceleration . If their distances are doubled and same torque is applied, then they move with angular acceleration

Options

  1. A4
  2. B3
  3. C/ 4

Correct answer

3

Step-by-step solution

Suppose the masses m₁ and m₂ are attached to the ends of a massless rod. C₁ is the axis of rotation which is at a distance R from each of the masses. the moment of inertia of the system, I =m₁ R^2+m₂ R^2= (m₁+m₂ ) R^2 Now if the distance between the masses is doubled, then the moment of inertia =m₁(2 R)^2+m₂(2 R)^2= (m₁+m₂ ) 4 R^2 Since the same torque is applied in both the cases, aligned & =I =I^ ^ & ^ = I I^ = (m₁+m₂ ) R^2 (m₁+m₂ ) 4 R^2 = 4 aligned

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