Solve Broken Leg & Pulleys: Find Weight W

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SUMMARY

The discussion centers on solving for the weight W attached to a lower pulley in a system where the total downward force at points A and B is 38N. The equations provided involve tension T and various angles, specifically 25 degrees and 20 degrees, to analyze forces in both the X and Y directions. A participant suggests that the tension T should equal 38N, while another contributor points out the need for a free body diagram (FBD) and emphasizes the importance of including all tension forces in the equations. The conclusion is that the equations require refinement to accurately solve for W.

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Homework Statement


assume that the total downward force exerted at A & B by the leg is 38N. find the weight W, attached on the lower puller

Homework Equations


please see attached diagram

The Attempt at a Solution


[/B]
i have written roman numerals to help determine which equation refers to which point

at point I
W = Tat point II
in the X direction
T \cos 25 + F_{1} = F_{A} cos \theta
in the y direction

T \sin 25 = F_{A} \sin \theta

at point III
in the X direction
0=T \cos 20 +T \cos 25

in the Y direction

T \sin 20 + T \sin 25

at point IV

in the X direction

T \cos 20 + T \cos 60 = 0in the Y direction

-T \sin 20 - T\sin 60 = 0

And that the end of this, can we say that T = 38N?

Please let me know if all the equations are correct?
Thank you for your input and assistance!
 

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stunner5000pt said:

Homework Statement


assume that the total downward force exerted at A & B by the leg is 38N. find the weight W, attached on the lower puller

Homework Equations


please see attached diagram

The Attempt at a Solution


[/B]
i have written roman numerals to help determine which equation refers to which point

at point I
W = Tat point II
in the X direction
T \cos 25 + F_{1} = F_{A} cos \theta
in the y direction

T \sin 25 = F_{A} \sin \theta

at point III
in the X direction
0=T \cos 20 +T \cos 25

in the Y direction

T \sin 20 + T \sin 25

at point IV

in the X direction

T \cos 20 + T \cos 60 = 0in the Y direction

-T \sin 20 - T\sin 60 = 0

And that the end of this, can we say that T = 38N?

Please let me know if all the equations are correct?
Thank you for your input and assistance!
Well I'm not sure of this problem but if the lower leg is horizontal and takes only an axial pulling force F1 , then draw the FBD of the pulley at the foot and sum vertical forces to solve for T and thence mg. F-a is given I think as a vert force of 38 N at A so I don't know why you are breaking it into components. You are also missing a tension force in your equation at that pulley.
 

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