Question

Two electric motors drive two elevators of equal mass in a three-story building 10 meters tall. Each elevator has a mass of 1,000 kg. The first elevator can do this work in 5.0 seconds. Calculate the power output of the first motor.

2.0 x 102 W
2.0 x 103 W
2.0 x 104 W
2.0 x 105 W

Answer 1

The power output of the first motor is, P = 2.0 x 10⁴ watts

Step-by-step explanation:

Given data,

The height of the building, h = 10 m

The mass of the elevator, m = 1000 kg

The time duration of the motor to do this work, t = 5.0 s

The force acting on the elevator,

F = m x g

= 1000 x 9.8

= 9800 N

The work done by the elevator,

W = F x h

= 9800 x 10

= 98000 J

The power output of the first motor,

P = W / t

= 98000 / 5

= 19600 watts

= 1.96 x 10⁴ watts

Hence, the power output of the first motor is, P = 2.0 x 10⁴ watts