The loaded cab of an elevator has a mass of 3.0 × 103 kg and moves 210 m up the shaft in 23 s at constant speed. At what average rate does the force from the cable do work on the cab?

Explanation:

Given data

The elevator mass=3.0×10³ kg

Time t=23 s

elevator lift d=210 m

The power is the average rate of work done:

So

P=F.V Cosα

Where F is force

V is velocity

α is angle between Force and velocity

Apply the Newton Law to find the force on elevator

The velocity of elevator is given as

Since the net force has same direction of motion so α=0°

So

mistakes are ok