Question

(a) Calculate the work done on a 1500-kg elevator car by its cable to lift it 40.0 m at constant speed, assuming friction averages 100 N. (b) What is the work done on the lift by the gravitational force in this process? (c) What is the total work done on the lift?

Answer 1

Answer:592 kJ

Step-by-step explanation:

Given

mass of elevator m=1500 kg

Lifting height=40 m

Friction Force F=100 N

The cable has to work against gravitational force and friction Force

Increase in Potential Energy of Elevator
`=mg h=1500* 9.8* 40=588 kJ`

thus work done by gravitational force
`=588 kJ`

Work done against friction force
`=F\cdot x=100\cdot 40=4 kJ`

Total Work done by the cable
`=592 kJ`