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MHT CET202121 Sep 2021Evening ShiftPhysicsRotational MotionActual

A particle performs rotational motion with an angular momentum ' L '. if frequency of rotation is doubled and its kinetic energy becomes one fourth, the angular momentum becomes.

Options

  1. AL
  2. BL 4
  3. CL 8
  4. DL 2

Correct answer

C. L 8

Step-by-step solution

Kinetic energy k = 1 2 I ^2 aligned & K ₂ ~K ₁ = I ₂ ₂^2 I ₁ ₁^2 & 1 4 = I ₂ I ₁ 4 & I ₂ I ₁ = 1 16 & L ₂ ~L ₁ = I ₂ ₂ I ₁ ₁ = 1 16 2= 1 8 & L ₂= L ₁ 8 aligned

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