Center of Gravity, Non-Uniform Bar

AI Thread Summary
The discussion focuses on calculating the center of gravity for a non-uniform bar with given angles and lengths. The user starts by establishing a force of 10N for the bar and uses trigonometry to analyze the forces acting on the ropes. They express uncertainty about how to determine the forces exerted by each pole to maintain equilibrium. It is clarified that the total vertical force must equal 10N, and the horizontal forces can be used to solve the problem since the bar is in equilibrium. The user concludes that they have found a solution based on this understanding.
JasonRox
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This is a question I need to do, I'm just going to put an example on what the question is like. In case a teacher of mine comes on here, I know I'm not "cheating".

Here is the image:

l\
lz.\.../l
l...\..../xl
l...\______/...l
l...l____q_l...l
l.....l

*Ignore dots.

z=56.2 degrees
x=90-56.2 degrees
q=center of gravity
lenght of bar is 4.3m

Find the distance from the right side of the bar, where the center of gravity is located.

This is all the information they give you. Simliar style, but not the same.

I started with using the Force of the bar as 10N. Easy number.

Then I find the force on the ropes, using trigonometry. I also find the horizontal forces as well.

The part I'm stuck on is how much force is actually used by each pole to keep the bar up.

The total vertical force must equal 10N, or else it won't stay up, or go up.

Do I use the horizontal forces to determine them?

I was thinking of using the difference between the two horizontal forces, and use the ratio to determine how far it is from the center.

Is this correct?
 
Last edited:
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Yes, you can use the horozontal forces to solve the problem.
The clue is that, since the bar is in equilibrium, the total horizontal force = zero.
Hence, the horoizontal components of the ropes are equal and in opposite directions.
Work it out from here
 
I found it now.

I think I did anyways.
 
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