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Pulleys and forces

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12
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1. Homework Statement
An object of mass 12.5 kg hangs from very light pulleys as shown here:
http://i26.tinypic.com/24lq5b4.jpg
What force must be applied to the rope so that the mass stays at rest?

2. Homework Equations
Fnet = ma.....

3. The Attempt at a Solution
I am really clueless when it comes to this question. I know the net force must be 0 because there is no acceleration occuring b/c it must be at rest. Please help.
 

Answers and Replies

19
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You are correct by saying that the net force must be 0, since the system will be in static equilibrium.
Try drawing a free body diagram for each pulley.
If you correctly label the tensions in the strings and sum up the forces in both the x and y directions, the problem will become much easier.
 

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