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MHT CET202020 Oct 2020Morning ShiftPhysicsRotational MotionActual

Two discs having moment of inertia l ₁ and I ₂ are made from same material have same mass. Their thickness and radii are t ₁, t ₂ and R ₁, R ₂ respectively. The relation between moment of inertia of each disc about an axis passing through its centre and perpendicular to its plane and its thickness is

Options

  1. AI ₁ t ₁= I ₂ t ₂
  2. BI ₁ t ₂²= I ₂ t ₁²
  3. CI ₁ t ₂= I ₂ t ₁
  4. DI ₁ t ₁²= I ₂ t ₂²

Correct answer

A. I ₁ t ₁= I ₂ t ₂

Step-by-step solution

I₁= m R₁² 2 I₂= m R₂² 2 I₁ I₂ = R₁² R₂² = t₂ t₁ I ₁ t ₁= I ₂ t ₂ m ₁= R ₁² t ₁ ~m ₂= R ₂² t ₂ m ₁= m ₂ R ₁² t ₁= R ₂² t ₂

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