Is the Tension in Physics Problem 651N or 1302N?

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The discussion centers on a disagreement regarding the tension in a wire labeled T5, with one participant believing it should be 1302N instead of the book's stated 651N. The explanation clarifies that tension is defined as the force across a cross-section of the wire, and in this case, the correct tension is indeed 651N, as it reflects the force being applied to the wire. A common misunderstanding about tension is addressed, emphasizing that the force exerted on the wire does not double when considering opposing forces. The participant acknowledges the clarification and expresses gratitude for the guidance, committing to improve the format of future submissions. Understanding the concept of tension is crucial for solving similar physics problems accurately.
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Homework Statement


I am just doing problems in 3000 solved physics problems in physics and I disagree with one of the answers and wanted to see if I am just an idiot or not

This is the picture of the problem

IMG_20150608_160135700[1].jpg

This the a picture of the solution in the book. It maybe hard to see the answers, but they say the tension in T5 should be 651N, this is what I disagree with.
IMG_20150608_160534846[1].jpg

The Attempt at a Solution


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So they say that T5 is 651N, but I think it should be 1302N because technically you have 651N pulling the 5th wire to the left and 651N of force pulling the wire to the right. Am I incorrect about this?

Thanks for reading
 
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Yes, you are incorrect. The tension is the force across a cross section of a wire. If you make a free body diagram of any part of the wire, the force across a section of the wire is the tension T5. If he wire is being pulled from one direction with 651 N, then this is the force across a section of the wire, and therefore the tension.

Also, please post your work in more detail in the future and make sure your images are more readable. You should also write out the problem in text. See the link to the homework guidelines in my signature.
 
Teachme said:
So they say that T5 is 651N, but I think it should be 1302N because technically you have 651N pulling the 5th wire to the left and 651N of force pulling the wire to the right. Am I incorrect about this?
Yes, you are incorrect. This is a common misunderstanding about tension.

Consider, for instance, a wire attached to a hook on a wall. You pull the free end of the wire with a force of 651N so that the wire is taut. How much tension is the wire under? How much force is the wire exerting on the wall? How much force is the wall exerting on the wire?
 
Ahh I see now. Thanks for quick response guys that really helped me out. Sorry for incorrect format, I'll make sure to do it correctly next time.
 
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