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Re: R = V/I ?



----- 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.

Rick