- #1
5carola5
- 22
- 1
Homework Statement
I don't really understand something in my textbook. It says the heat Resistor (how to say that in English? I hope it's alright like this...) trough a cylindrical tube (from the inside to the outside or revers) would be: R(heatrisistor)=1/2∏Lλ * ln (R1/R2) And then my textbook gives the following picture (well oke a but nicer, but that's what I make of it)http://schattielover.deviantart.com/art/homework-314836756
But if I were to follow this I get a negative R every time (since R1 is smaller than R2 and so the ln gets negative right?), which I find very strange... So I searched trough other textbooks that I have and they had no information about it and searched trough the internet (I'm not very good at that ^^') and found nothing I can use.
So my question is: Can someone explain to me, nice and simple, what I should do with the R1 and the R2? (I probably am misunderstanding my textbook... I'm sure of it ^^')
Well thanks for reading all of this anyway, hope someone can help me with this. :)
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