A 5.0-kg crate is lifted straight up from the ground at a constant speed of 1.5 m/s to the back of a moving truck which is at a height of 5.0 m above the ground.What power is needed to accomplish this task?

Question

Quizplus · Accepted Answer

The power needed to lift the crate at a constant speed can be found using the formula:

Power = force x velocity

The force needed to lift the crate is its weight, which is given by:

F = m x g = 5.0 kg x 9.81 m/s^2 = 49.05 N

The velocity is given as 1.5 m/s.

Therefore, the power needed is:

P = F x v = 49.05 N x 1.5 m/s = 73.58 W ≈ 74 W

Therefore, the best choice is (C) 74 W.

A 50-Kg Crate Is Lifted Straight Up from the Ground at at a Constant