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Per NCERT §6.12 (and many examples), if an ice skater pulling arms inward DECREASES her moment of inertia, what happens to her angular velocity?
ABecomes zero almost immediately
BIncreases since L = I·ω
CStays the same as before always
DDecreases since ω drops with I
Answer & Solution
Correct answer: B. Increases since L = I·ω
NCERT §6.12 + Conservation of L: τ_ext = 0 ⇒ I ω = const. Smaller I ⇒ larger ω. Skater spin-up.
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