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----- Original Message -----
From: "Mark Sylvester" <msylvest@SPIN.IT>
>
> Hmmm... what, then, is the quantitative definition of R?
>
> Mark
For a uniform material, I would use:
R = Resistivity x Length/ (Cross Sectional Area)
where the Resistivity = (Temperature normalized Resistivity)(1+alpha x
deltaT)
alpha being a measured/cataloged coefficient and deltaT measured from the
normalization Temp (often 20C).
For a complex object, the resistance is a parallel/series combination of
these terms depending on the materials and the construction. Again, V/I can
functionally give you a _measure_ of the resistance of such an object, but
doesn't (in my mind) define that resistance.