mass = m = 18 * 73 = 1314 kg of people (not too very fat ones)
h = 6.8 meters
work done = force * distance = m g h = 1314 * 9.81 * 6.8 = 87,654 Joules
This was evidently done in 80 seconds That is not explicitly stated)
power out = work done in Joules / time in seconds = 87654/80
= 1,096 Watts
at maximum capacity, same height, same speed, same earth gravity so
1314/0.22 = 5973 kg
An escalator in a department store is driven by a large electric motor whose power consumption changes with the load to keep the escalator moving at a constant velocity, up to a certain maximum power capacity. an escalator working at 0.22 of its maximum power capacity lifts 18 people per minute a vertical height of 6.8m. these people have an average mass of 73kg.
a) how much work is done in 80s?
b) what is the power delivered by the escalator in watts?
c) what is the maximum mass of people can the escalator deliver in 80s while working at its maximum power capacity.
1 answer
1 answer