What is the length described in surface tension?

Thread starter goggles31
Start date Dec 29, 2016
Tags

Length Surface Surface tension Tension

AI Thread Summary

The discussion centers on the confusion regarding the term used in surface tension calculations, specifically the expression 2πr. Participants clarify that the term σcosθ(2πr) relates to the force exerted along the circumference of a circular surface, where σ represents surface tension and θ is the contact angle. The original confusion stemmed from misinterpreting the area formula πr² as a length, which is incorrect. The focus is on understanding the correct application of 2πr in the context of surface tension. Clarifying these terms is essential for accurate comprehension of the physics involved.

Dec 29, 2016

goggles31

https://web.mst.edu/~numbere/CP/CHAPTER 3.htm

I have trouble understanding why the length used in 3.1.1 is pir^2. My notes don't explain what length we use either.

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Dec 29, 2016

Vanadium 50

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πr² is not a length. That may be the source of the confusion.

Dec 29, 2016

goggles31

Vanadium 50 said:

πr² is not a length. That may be the source of the confusion.

Sorry I meant 2pir. Specifically the term σcosθ(2pir).

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