Equilibrium of a Uniform Beam with Non-Vertical Forces

AI Thread Summary
A uniform beam is supported at its center of gravity with forces of 4N and 6N acting at 60 degrees downward, while an unknown force F acts upwards on the left side. To solve for F, one must sum the moments of the vertical components of all forces about the center support, ensuring equilibrium is maintained. The discussion highlights confusion regarding the calculation process and notes a potential error by the teacher suggesting that F may be negative, indicating it acts downward. Participants emphasize the need to outline the steps taken to find a solution and encourage sharing any attempts for better guidance.
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Homework Statement



A uniform beam is supported at its centre of gravity. The forces, F, 4N and 6N act to keep the beam in equilibrium. Forces 4N and 6N are acting at 60deg to the horizontal, calculate the force F, if the beam remains in equilibrium.

F is acting upwards on the left of the beam with 4N at 60deg downwards. 6N is on the right acting at 60deg downwards.



Homework Equations



Now we know the physics teacher got this wrong and the answer to F will actually be a negative acting downwards from the top.


The Attempt at a Solution



I don't know where to start could someone outline the working for a solution?
 
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What force are you trying to calculate?
 
As I understand the problem, there is a beam of length L supported at L/2 from one end, at the cg of the beam. Then there is a 6 N force appied at the right end, acting 60 degrees downward from the x axis, and a 4 N force at the left end, acting 60 degrees downward from the x axis, and another force at the left, unknown, labeled F, acting vertically in an unknown up or down direction. If that's the case, sum moments of the vertical components of all forces about the center support = 0, and solve for F, and determine whether it acts up or down.
 
Equilibrium on a uniform beam problem

Homework Statement



4388288100_ce329b0b3a.jpg


Could someone please explain how i would solve this from the basics? I can't find any similar examples in my textbooks. All i remember is that the teacher made a slight mistake and the result may be negative?


Homework Equations





The Attempt at a Solution

 

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tomsdubs said:
Could someone please explain how i would solve this from the basics? I can't find any similar examples in my textbooks. All i remember is that the teacher made a slight mistake and the result may be negative?

You asked this before, but you never replied to the help you were given …
tomsdubs said:

Homework Statement



A uniform beam is supported at its centre of gravity. The forces, F, 4N and 6N act to keep the beam in equilibrium. Forces 4N and 6N are acting at 60deg to the horizontal, calculate the force F, if the beam remains in equilibrium.

F is acting upwards on the left of the beam with 4N at 60deg downwards. 6N is on the right acting at 60deg downwards.



Homework Equations



Now we know the physics teacher got this wrong and the answer to F will actually be a negative acting downwards from the top.


The Attempt at a Solution



I don't know where to start could someone outline the working for a solution?

You need to use moments.

Show us what you've done, and where you're stuck, and then we'll know how to help.
 
Moderator's Note: Threads merged.
 
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