alleryA figure skater pulls in her arms during a spin. Her moment of inertia decreases. By conservation of L (I × omega), her angular velocity:
AIncreases
BBecomes zero
CDecreases
DStays same
Answer & Solution
Correct answer: A. Increases
L = I × omega is conserved (no external torque).
If I decreases, omega must increase proportionally.
So she spins faster.
*Note: KE = (1/2) I omega² also increases — extra energy comes from her muscles doing work to pull arms in.*
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