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MHT CET20239 May 2023Morning ShiftPhysicsRotational MotionActual

Two discs of same mass ąnd same thickness (t) are made from two different materials of densities ' d ₁ ' and ' d ₂ ' respectively. The ratio of the moment of inertia I ₁ to I ₂ of two discs about an axis passing through the centre and perpendicular to the plane of disc is

Options

  1. Ad ₁: d ₂
  2. Bd ₂: d ₁
  3. C1: d ₁ ~d ₂
  4. D1: d ₁^2 ~d ₂

Correct answer

B. d ₂: d ₁

Step-by-step solution

The ratio of moments of inertia of two discs of the same mass and same thickness but of different densities is given by I ₁ I ₂ = R ₁^2 R ₂^2 = d ₂ ~d ₁

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