A lift at a construction site moves 10 labourers every minute from the first floor of the building to the second. The second floor is 6.0 metres above the first floor. If the average mass of labourers is 56 kg, determine the power requirement of the lift in order to move this number of passengers in this amount of time.

Asked by Topperlearning User | 15th Jul, 2014, 08:51: AM

Expert Answer:

Number of passengers is 10
 
Work done by one passenger = force x height
                                          = F × d
                                          = (56 kg × 9.8 m/s2) × 6.0 m
                                          = 3292.8 J
 
Work done by ten passengers = 3292.8 J × 10
                                           = 32928 J
 
P = Work done by ten passengers / time = (32928 J) / (60 s)
 
P = 548.8 W

Answered by  | 15th Jul, 2014, 10:51: AM