試題詳解

6. Suppose an ice skater is soing at 0.8 revolutions (rev) per second with her arns extended. She has a moment of ineria of 2.34 kg • m² with her arms extended and of 0.363 kg • m² with her a close to her body (appropriate for a 60-kg skater). What is her angular velocity in revolutions per second after she pulls in her arms?
(A) 2.2 rev/s
(B) 3.2 rev/s
(C) 4.2 rev/s
(D) 5.2 rev/s
(E) 6.2 rev/s