Solving Pulleys and Forces Homework Problem

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To solve the problem of a 12.5 kg mass hanging from pulleys, it is essential to recognize that the net force must equal zero for the mass to remain at rest. This indicates that the system is in static equilibrium. Creating free body diagrams for each pulley will help visualize the forces at play. By labeling the tensions in the strings and summing the forces in both the x and y directions, the solution becomes clearer. Understanding these principles is crucial for accurately determining the required force to keep the mass stationary.
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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?

Homework Equations


Fnet = ma...

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 occurring b/c it must be at rest. Please help.
 
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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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