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. Part A Once you have pulled hard enough to start the box moving upward, what is the magnitude F of the upward force you must apply to the rope to start raising the box with constant velocity?

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.
Part A Once you have pulled hard enough to start the box moving upward, what is the magnitude F of the upward force you must apply to the rope to start raising the box with constant velocity?
Express the magnitude of the force in terms of m, the mass of the box.
Part BConsider lifting a box of mass mto a height husing two different methods: lifting the box directly or liftingthe box using a pulley (as in the previous part).
What is {W_{rm d}}/{W_{rm p}}, the ratio of the work done lifting the box directly to the work done lifting the box with a pulley?
Express the ratio numerically.

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