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An elevator in a building can carry a maximum of 10 persons, with the average mass of each person being 68 kg. The mass of the elevator itself is 920 kg and it moves with a constant speed of 3 m/s. The frictional force opposing the motion is 6000N. If the elevator is moving up with its full capacity, the power delivered by the motor to the elevator (g = 10 m/s2) must be atleast

a. 66000 W b. 63360 W c. 48000 W d. 56300 W Answer: (a) Net force on motor will be Fm = (920 + 68(10)]10 + 6000 = 22000 N So, required... View Article