How Do You Calculate Tension and Reaction Forces in a Leaning Broom Problem?

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To calculate the tension and reaction forces in the leaning broom problem, the setup involves understanding the statics equations where the sum of moments and forces equals zero. The broom's length (L) is not necessary for determining the tension; instead, focus on the torques created by the weight and the cable tension. The angle of the broom is crucial, as it affects the torque calculations, requiring the correct application of trigonometric functions to resolve forces. By summing the torques about the pivot point, the tension can be isolated and calculated. Properly setting up the equations is essential for solving this statics problem effectively.
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Homework Statement


Image of problem: http://img227.imageshack.us/my.php?image=physics3ue4.png

A 1229.0 N uniform broom of length L is supported by a cable. The broom is pivoted at the bottom, the cable is attached a distance (3/4)L from the pivot, and a 2442.0 N weight hangs from the brooms top.

I need to find the Reaction forces (vertical and horizontal), as well as the tension.


Homework Equations


The basic statics equations, Sum of Moment and Force = 0

Moment = Torque= r x F

The Attempt at a Solution



This is more a problem of setting up this equation. I'm perfectly fine at solving Statics equations, but it's setting them up that I have dificulties with. Here's my questions:

1) Ok, I'm looking at 4 variables, and three equations. I don't know L, don't know the reaction forces, and the Tension. In statics, this would technically be "statically indeterminte" because we only have two force equations and one moment equation. The problem here is that since L is unknown, and I have to input a number.

2) How does the broom's angle play into all of this. I know it plays a factor, but for the life of me, I can't figure out where to apply that angle too. >.>

Thanks in advance.
 
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ultrapowerpie said:

Homework Statement


Image of problem: http://img227.imageshack.us/my.php?image=physics3ue4.png

A 1229.0 N uniform broom of length L is supported by a cable. The broom is pivoted at the bottom, the cable is attached a distance (3/4)L from the pivot, and a 2442.0 N weight hangs from the brooms top.

I need to find the Reaction forces (vertical and horizontal), as well as the tension.


Homework Equations


The basic statics equations, Sum of Moment and Force = 0

Moment = Torque= r x F

The Attempt at a Solution



This is more a problem of setting up this equation. I'm perfectly fine at solving Statics equations, but it's setting them up that I have dificulties with. Here's my questions:

1) Ok, I'm looking at 4 variables, and three equations. I don't know L, don't know the reaction forces, and the Tension. In statics, this would technically be "statically indeterminte" because we only have two force equations and one moment equation. The problem here is that since L is unknown, and I have to input a number.

2) How does the broom's angle play into all of this. I know it plays a factor, but for the life of me, I can't figure out where to apply that angle too. >.>

Thanks in advance.
You may not neeed to know the exact value of L. Sum torques about the base of the boom to solve for T. You'll need to know the angles before you can correctly determine the torques.
 
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