Solving Pulley Problem: Find T1, T2, W1, W2, Alpha

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The discussion focuses on solving a pulley problem involving a patient's leg supported by two weights, with a total weight of W = 300N. The leg's center of gravity is located 2/3 L from point A, and the angle from cable 2 is Beta = 45 degrees. Participants emphasize the need for five equations to solve for the five unknowns: T1, T2, W1, W2, and the angle Alpha, while correcting the force equations and applying Newton's 3rd law for accurate calculations.

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Homework Statement


A patient's leg is held in position by 2 weights tht are connected through cables. The weight of the leg is W = 300N. L is the horizontal distance between the points where the cables connect with the leg (points A and B) and C is the center of gravity for the leg, located 2/3 L away from A. The angles from cable 2 is Beta=45 degrees.
Find T1, T2, W1, W2, and the angle Alpha for the leg to stay in equilibrium.
[PLAIN]http://img820.imageshack.us/img820/2055/drawing5.jpg


Homework Equations


Sum of Fy=0
Sum of Fx=0
Sum of Moments = 0

The Attempt at a Solution



So I separated the pulleys, so have for the weight and pulleys on left:
Sum of Fy= T1-W1=0
For the weight and pulleys on right:
Sum of Fy=T2-W2=0 (is this correct? What is the effect of the second pulley on the tension?)

Sum of Fy= T1sin(Alpha) - W +T2sin(45)
(Should these be T1sin and T2 sin or just T1 and T 2?)

Then I did sum of moments:
Sum of moments around point A = -W*2L/3 + T2sin(45)*L=0
Sum of moments around C = -T1sin(Alpha)*2L/3 + T2sin(45)*L/3
Sum of moments around B = W*L/3 + T1sin(Alpha)*L

So basically I'm stuck. Not sure if so far it's correct of how to proceed.
 
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Can anyone help me out? Please.
 
You have 5 unknowns so you will need 5 equations. Your moments all look okay to me, but your forces need some revision. You need to revise your Fy equation, and create an equation for Fx. Remember to use Newton's 3rd law to work out any kinks.
 

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