Mechanics of materials beam Problem

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The discussion revolves around calculating the necessary cross-section of a tension rod in a 1-ton wall hoist system, which is supported by a horizontal beam and a tension rod at a 30-degree angle. The rod is designed with a factor of safety of 5, based on a yield point of 30,000 PSI, leading to a working stress of 6,000 PSI. Participants clarify that the tension in the rod differs from the compression load in the beam, emphasizing the need for proper unit representation in calculations. There is confusion regarding the force calculations, particularly the value of R, which represents the reaction force in the system. The conversation highlights the importance of clear explanations and accurate unit usage in engineering problem-solving.
Chacabucogod
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A 1-ton wall hoist consists of a horizontal beam, supported by a tension rod at 30 deg, as shown. The rod is to be designed with a factor of safety 5 with repeat to its yield point of 30,000 PSI. Determine its necessary cross section




S=F/A



30000/5=6000PSI
-2000+Rsin(30)=0
R=4000
R_x=4000cos(30)
6000=4000cos(30)/A

The solution from the book is 2/3 which would imply that the force is 4000. Am I doing something wrong?
 

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You've just thrown some numbers down without any explanation or units. It's hard to follow what you are doing.

What is R supposed to be?

It seems like you're supposed to figure out the tension in the tension rod, which apparently is not the same as figuring out the compression load in the horizontal beam. The area 'A' should have some units attached.
 
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Never mind. It's the rod's tension, not the cantilever. Seems like I read it wrong. Thank you
 

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