Physics chapter8 - Problem 41
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Physics for Scientists and Engineers (9th Edition)

Chapter-8

Table of Content


Question 41





A loaded ore car has a mass of m = kg and rolls on rails with negligible friction. It starts from rest and is pulled up a mine shaft by a cable connected to a winch. The shaft is inclined at th = above the horizontal. The car accelerates uniformly to a speed of v = m/s in t = s and then continues at constant speed.
(a) What power must the winch motor provide when the car is moving at constant speed?
(b) What maximum power must the winch motor provide?
(c) What total energy has transferred out of the motor by work by the time the car moves off the end of the track, which is of length 1250 m?