MrAL, I think the point of contention here is that Ohm's experiments where this 'law' came from used conductors with a fixed R to get the results that made sense. You have to remember that these experiments were done over 150 years ago, the basic reasons for these forces were almost completely unknown, in order for his experiments to work he early on realized that he had to restrict the variables in his experiments to fixed conductors and fixed temperatures, because he knew that he couldn't explain flows in ionic fluids or complex materials. So the root of Ohms law is in fact based on these highly limited set of original test conditions, however the root applicability of the equation extends to non-ohmic materials as well. Ohm's law CAN be applied to non-ohmic materials you have as yet to disprove this. A PN junction or any of the junctions in a transistor will have an equivalent resistance and voltage across it and that current will balance out perfectly so that there is no imbalance in the circuit at any given point in time. If using the V=IR equation on non-ohmic materials isn't Ohm's Law then why do the numbers ALWAYS work out? R is in fact a complex thing, even in metallic conductors, Ohm just picked a set of experiments that kept R almost completely static to prove the general proportional response of the V and I which at the time were better understood than resistance.
Again, I'll repeat myself one more time, just because his experiments used fixed resistances does NOT mean that Ohm's Law does not apply to variable resistance. At any given moment in time an electric circuit will have a set V=IR values that will ALWAYS work out
One caveat, I'm a little iffy on saying always, simply because ohms law like most macro laws break (or at least become insanely complex) on a quantum level.
You talk and talk and talk, but i havent seen a *single* academic proof
or a *single* reference to support your own 'theory', while i have offered
several of each. You cant knock something you dont understand
I never said V=R*I doesnt work out, just that it is not always Ohm's Law.
Also, show me one way in which you *DO* use Ohm's Law, yourself.
You should really find ONE reference if you want to be taken seriously
on this matter.
Electrician:
Very good idea there. I would have said either a capacitor or an inductor.
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