When an ice skater twirling on the point of a skate draws her arms in she ends up whirling faster. This is because

A. linear momentum is conserved.
B. angular momentum is conserved.
C. rotational energy is conserved.
D. a net external torque acts on the skater.


Answer: B

Physics & Space Science

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If R = 3.0 k?, C = 6.0 nF, ?1 = 10.0 V, Q = 18 nC, ?2 = 6.0 V, and I = 5.0 mA, what is the potential difference Vb?Va?

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