How long will it take a 7.08 hp motor to lift a 250 kg beam directly upward at constant velocity from the ground to a height of 45.0 m? Assume frictional forces are negligible. (1 hp = 746 W)
A) 20.9 s
B) 1.56 × 104 s
C) 2.18 × 104 s
D) 39.7 s
Answer: A
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