Two equal masses are raised at constant velocity by ropes that run over pulleys, as shown below. Mass B is raised twice as fast as mass A. The magnitudes of the forces are FA and FB, while the power supplied is respectively PA and PB. Which statement is correct?
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A. FB = FA; PB = PA.
B. FB = FA; PB = 2 PA.
C. FB = 2 FA; PB = PA.
D. FB = 2 FA; PB = 2 PA.
E. PA = FA; PB = FB.
Answer: B
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