Question

A warehouse has a pulley system to move stuff. A technician uses the pulley to lift a 500.0 kg box of material from floor to the top shelf, 3.50 m up. The force on the chain is 10 000. N applied through a distance of 4.50 m. What is the efficiency of the pulley?

Answer 1

Answer: 38% efficiency

Step-by-step explanation:

Given:
- Mass of box, 500.0kg

- Height lifted, 3.50m

- Force Applied, 10 000N

- Distance applied, 4.50m

Required:

% Efficiency, can be found through formula η = [useful energy output (Eout) ÷ energy input (Ein)] x100%

To calculate Eout, you need to find which energy transferred to the box is useful. In this case, it is the gravitional potential energy, which can be found by the formula Eg = mgh, where Eg = (500.0)(9.8)(3.50) = 17150J.

To calculate Ein, find the total energy that was inputted to the object, given by W = FΔd, where W = 45000J.

Now, plug in the values to the %eff formula:

(17150J ÷ 45000J) x100% ≈ 38%

Therefore % efficiency of the pulley is 38%.