Bracket/block static friction problem (physics)

AI Thread Summary
The discussion revolves around a static friction problem involving a 12kg block and a 7kg bracket. The user expresses confusion about drawing free body diagrams (FBDs) correctly, which is crucial for solving the problem. They identify forces acting on both the block and the bracket but struggle with multiple variables in their equations. The user has calculated a friction force of 94.08 N but is unable to progress further due to the complexity of the system. Assistance is requested to clarify the correct approach to the FBDs and the equations needed to solve the problem.
notbynumber
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Homework Statement


http://img3.imageshack.us/img3/6618/5n6.jpg
Image there.


Homework Equations


Well this is actually where the problem occurs. You make your own equations.


The Attempt at a Solution


It's the friction that is really messing me up. I'm just so confused, I'm going to show you my attempt at FBDs for the problem.

I think that if I just know how to draw them correctly I'll be able to find my answer, unless there is some other tricky way to get it.

Okay so for the 12kg block, we have:

m1g going DOWN
n1 going UP
T to the LEFT
fs to the LEFT

And for the 7kg bracket, we have:

m2g going DOWN
n2 going UP
n1 going DOWN
T to the RIGHT?
fs to the RIGHT

Apparently I didn't draw them correctly because when I try to solve for something, there are always two variables... other than f = Mu*N which equals 94.08 N.
 
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Did I mention this is due soon? Please everyone, I really need your help.
 
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