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TJDF
Oct20-08, 02:28 PM
1. The problem statement, all variables and given/known data
A 306 kg crate hangs from the end of a 10.3 m long rope. You pull horizontally with a varying force to move it a distance d = 5.7 m to the right. What is the magnitude of the applied force, F, when the crate is at rest in its final position?
Associated Diagram:
http://img217.imageshack.us/img217/103/prob03axb9.th.gif (http://img217.imageshack.us/my.php?image=prob03axb9.gif)http://img217.imageshack.us/images/thpix.gif (http://g.imageshack.us/thpix.php)

2. Relevant equations

I don't even know how to start this.

JoAuSc
Oct20-08, 03:01 PM
There are three forces being applied to the crate: the applied force of you pulling on it, the force of the crate's gravity downward, and the force of the tension of the rope. At the final position, as shown in the diagram, the force vectors should all add to zero. The first step should be to draw a free body diagram and label the appropriate force vectors. Let us know if you need more help.