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## Homework Statement

http://www.physics.upenn.edu/~jrk/p101/Homework/hw7_sp09.pdf

Here is the link. I am having trouble with questions 8 and 9. I posted the whole link because these questions have a diagram that go with it.

## Homework Equations

Sum of F = 0

Sum of torque=0

## The Attempt at a Solution

Well, I just considered rod B, because that's what they asked about.

So the Forces there are:

The normal force from the wall

An upward force to keep it from falling

And the tension force acting downward on rod b.

But the problem is, then how will the horizontal forces balance? I think I'm definitely missing something.

When I did the problem going straight to the torques with these forces,

I chose an axis of rotation at a and plugged in the corresponding torques for the forces listed above, and I got answer c.

But I know I'm doing something wrong in the first part because my teacher said to always start with the forces and then pick the appropriate axis of rotation, but my forces don't make sense. Please help.

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