A girl of mass 40 Kg climbs a rope 6 m long at constant speed in 15 seconds. What power does she expend during the climb?
Given,
Mass m = 40 kg
Height h = 6m
Time = 15 s
Power =????
Let g = 10 ms-2
Potential energy = m × g × h
= 40×10×6 J
= 2400 J
Power = 160 J/s
So power spent by girl is 600 watts
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