As you are trying to move a heavy box of mass m , you realize that it is too hea

Question

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. There is no one around to help, so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. You pull up on the rope to lift the box.

(Figure 1)

Use g for the magnitude of the acceleration due to gravity and neglect friction forces.

Consider lifting a box of mass m to a height h using two different methods: lifting the box directly or lifting the box using a pulley (as in the previous part).

What is Wd/Wp, the ratio of the work done lifting the box directly to the work done lifting the box with a pulley?

Express the ratio numerically.

Explanation / Answer

This is a concept question, no calculation needed. They want you to understand the nature of a simple machine. You do the same amount of work, but apply a smaller force but over a greater distance. Since W = Fd, overall, the same amount of work is done.

Thus the ratio = 1

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