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Question 30377
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Rigid Body Dynamics: Advanced — Conservation in Rotation MCQ

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Advanced — Conservation in RotationHardQuestion 30377

Question

A star (radius R, angular velocity ω) contracts to radius R/4 (assuming moment of inertia ∝ MR²). New angular velocity is:
  1. A
    ω/16
  2. B
    4ω
  3. C
    16ω
    Correct
  4. D
    ω/4

Correct answer

16ω

Explanation

L = Iω = cMR²ω = const. If R → R/4: I_new = cM(R/4)² = cMR²/16. ω_new = cMR²ω/(cMR²/16) = 16ω.

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