Static equilibrium problem -- with a pulley

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Homework Help Overview

The discussion revolves around a static equilibrium problem involving a pulley system. Participants are analyzing the forces and moments acting on the system, with a focus on ensuring that the sum of forces and moments equals zero.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants are attempting to compute components of forces and their contributions to torque. There are questions about the inclusion of moment arms in the calculations and the correctness of terms in the equations.

Discussion Status

The discussion is ongoing, with participants providing feedback on each other's calculations and interpretations. Some guidance has been offered regarding the identification of force components and moment arms, and there are indications of revisions being made to the original posts based on this feedback.

Contextual Notes

There are mentions of specific measurements, such as a 6-inch distance related to the pulley, and some participants express uncertainty about their calculations and the use of their calculators.

J-dizzal
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Homework Statement


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Homework Equations


sum of forces equal to zero.

The Attempt at a Solution


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Last edited:
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Looks like you left out a moment arm in one of your terms in ΣMA.
 
I can't really follow your work computing components of forces and making sure each force contributes to torque.
 
Thank you, i didnt notice the 6in on the pulley at first.
TSny said:
Looks like you left out a moment arm in one of your terms in ΣMA.

Dr. Courtney said:
I can't really follow your work computing components of forces and making sure each force contributes to torque.
I updated my original post but I am still getting the same answer haha.
 
Note that FDBsinθ is a force component, not a moment. What's the moment arm for this force?
 
TSny said:
Note that FDBsinθ is a force component, not a moment. What's the moment arm for this force?
oh crap sorry, let me finish that equation.
Ok, for the sum of moments i got 830.5 lb, now let me correct the rest of the equations and see what i get for an answer to the magnitude of A.
edit. 880.7 lb
edit2. 1761.5
 
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In the ΣMA equation, your last term is -FDB. Is this meant to be there?
 
TSny said:
In the ΣMA equation, your last term is -FDB. Is this meant to be there?
no its not supposed to be there, I've change it again, I've edited my original post. there is still something wrong with it though...
 
Check your calculation of Ax. Looks like you have it set up correctly, but made some sort of mistake in plugging the numbers in your calculator.
 
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TSny said:
Check your calculation of Ax. Looks like you have it set up correctly, but made some sort of mistake in plugging the numbers in your calculator.
thanks.
I got a new HP 300s calculator in the mail today, still getting used to it...
 

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