Two hanging masses supporting object

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SUMMARY

The discussion centers on a physics problem involving two hanging masses supporting an object, specifically a leg and cast weighing 260 N and a counterbalance weighing 115 N. The objective is to determine the weight w1 and the angle required to ensure no force is exerted on the hip joint. The user initially attempted to apply the cotangent function and the Pythagorean theorem but miscalculated the tensions involved. The correct approach requires incorporating the angle of 40° for the counterbalance w2 into the calculations.

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Homework Statement



The leg and cast in Figure P4.18 weigh 260 N, with the center of mass as indicated by the blue arrow in the diagram. The counterbalance w2 weighs 115 N. Determine the weight w1 and the angle needed in order that there be no force exerted on the hip joint by the leg plus cast.

Homework Equations



This is one of the problems; I can't figure out which equations pertain to this problem.

The Attempt at a Solution



cot 40 = -x2/115
x = -137.05

a^2 + b^2 = c^2
115^2 + (-137.05)^2 = c^2
32007.70 = c^2
178.9 = c

260 - 178.9 = T
81.09 = T

This was wrong. I subtracted because I thought that in order for there to be no force exerted on the hip, the force would have to be zero, so the combined tensions would have to cancel out the force. Where am I going wrong?
 
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I forgot to include that the angle for w2 between the string and the horizontal is 40°.
 
You have the figure. But we don't know what the figure is.So either try explaining the situation or attach the diagram. I would prefer the latter.
 

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