Find Equilibrium: Solving a Uniform Bar Problem

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Homework Statement


A uniform bar AB of length l and weight W is hinged to the wall at its end A and supported by means of a string of length a which is tied to the wall as shown. Find the angle [tex]\theta[/tex] that the bar will make with the wall corresponding to the position of equilibrium
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Homework Equations


Moment = Force X perpendicular distance


The Attempt at a Solution



I had tried to find moment about point A. I had resolved W and T (tension in the string BC) into rectangular components. One along the bar and other perpendicular to the bar. along the bar components will not add to the moments at A while the perpendicular components will get multiplied by the distance (For T and W, l and l/2 respectively) and added according to sign convention (anticlock wise rotation as positive and clockwise rotation as negative). but because the angle ABC is getting too bulky (complicated), I don't think I can anyhow end this problem with answer. Need your immediate help.
 
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More info:

W acts from the center of the bar.

angle A = [tex]\theta[/tex]
 


Are you sure there isn't another bit of information?
 


There isn't enough information to solve the problem. You need to know where 'C' is.
 


In the diagram attached (I hope it does) it shows the 3 forces W RA and RC meeting at the midpoint of the string. The two triangles (G for geometry, and F for forces) should be similar, and there should be enough information to conclude all the dimensions and forces. The only dimension not shown is the horizontal projection of the G triangle, and that is L/2*(cos theta). But there still is not enough information to bring this to completion.
 

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I want the solutions of all the problem i.e in this chapter. So please help me in solving the problem of this chapter...