What power is needed to lift a 49-kg person a vertical distance of 5.0 m in 20.0 s?

Question

Quizplus · Accepted Answer

The work done to lift a person of mass m through a height h is given by:

W = mgh

where g is the acceleration due to gravity (9.8 m/s²).

The power P is the rate at which work is done, which is given by:

P = W/t

where t is the time taken to lift the person.

Substituting the given values, we have:

W = (49 kg)(9.8 m/s²)(5.0 m) = 2401 J

P = 2401 J / 20.0 s = 120 W

Therefore, the power needed to lift the person is 120 W, which is choice (D).

What Power Is Needed to Lift a 49-Kg Person a Vertical