In this somewhat nonsensical problem, you have a box hanging by a rope from the ceiling...

 

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In this somewhat nonsensical problem, you have a box hanging by a rope from the ceiling of a freight elevator. The box has an inertia of 0.5kg, and the mass of the rope is negligible compared to that. Assume the elevator starts from rest and moves upward with a constant acceleration of 3.0m/s. (a) Draw a free-body diagrams for the box, labelling the forces appropriately. Make sure the lengths of the force vectors correspond to the magnitudes of the forces. Below your diagram, give numerical values for the magnitudes of all the forces, and show how you obtained these values. (b) Assuming your system is the box only, what is the net work done on the system in the first 5s of the motion? What forces do work on the system, and what are their individual contributions to the work? (c) Relate the work found in (b) to the change in energy of the system. If more than one kind of energy is involved, give the corresponding change for each. (d) Now assume the system is the box and the Earth (nothing more!). Which force(s) do work on this system, and what is the total work they do over first 5s of the motion? (e) Relate the work found in (d) to the change in energy of the (box + earth) system. If more than one kind of energy is involved, give the corresponding change for each. In this somewhat nonsensical problem, you have a box hanging by a rope from the ceiling of a freight elevator. The box has an inertia of 0.5kg, and the mass of the rope is negligible compared to that. Assume the elevator starts from rest and moves upward with a constant acceleration of 3.0m/s. (a) Draw a free-body diagrams for the box, labelling the forces appropriately. Make sure the lengths of the force vectors correspond to the magnitudes of the forces. Below your diagram, give numerical values for the magnitudes of all the forces, and show how you obtained these values. (b) Assuming your system is the box only, what is the net work done on the system in the first 5s of the motion? What forces do work on the system, and what are their individual contributions to the work? (c) Relate the work found in (b) to the change in energy of the system. If more than one kind of energy is involved, give the corresponding change for each. (d) Now assume the system is the box and the Earth (nothing more!). Which force(s) do work on this system, and what is the total work they do over first 5s of the motion? (e) Relate the work found in (d) to the change in energy of the (box + earth) system. If more than one kind of energy is involved, give the corresponding change for each.