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Homework Statement
A bridge, constructed of 11 beams of equal length L and negligible mass, supports an object of mass M as shown in the picture.
Assuming that the bridge segments are free to pivot at each intersection point, what is the tension T in the horizontal segment directly above the point where the object is attached (see image)? If you find that the horizontal segment directly above the point where the object is attached is being stretched, indicate this with a positive value for T. If the segment is being compressed, indicate this with a negative value for T.
Homework Equations
t_{net} = 0 at all points
t = Fr
The Attempt at a Solution
So I worked out that:
F_{P} = 2/3 Mg
F_{Q}=1/3 Mg
But after that I have no idea what to do. I am completely lost. I was told to try considering the torques on single points but I don't understand how to do that in this case.
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