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Re: Ohm's Law

I this this as an equation commonly known as "Ohm's Law". I don't see
that very much is changed by giving it this label or not, I still need
to put in all the appropriate qualifiers. I have no more problem with
this than with calling "h" Planck's constant.

I have noticed that sometimes the "laws" I learned are now being called
"principles" or some such thing in newer textbooks. (I get a good laugh
from the class when I suggest that in a few years they will be known as
something like "recommended behavior for the system".) In the case of
V=IR I don't think that this kind of rephrasing addresses the basic
issue - it isn't a law, principle or any such thing but rather a
definition of resistance for systems where it makes sense to talk about
resistance (and fortunately there are many).

Van E. Neie wrote:

Is there any advantage to calling *V = IR Ohm's Law? I have found that
just calling it a fundamental relationship among *V, I and R is
sufficient. If you know two of these variables, you can find the
third. Whether the device is ohmic doesn't matter, right?

Am I missing something? The only reason I bring it up is that
practically every elementary physics text refers to it as Ohm's Law, but
often there is no mention of the conditions that must be satisfied.

Thanks.

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Van E. Neie Ph: 765-494-5511
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Doug Craigen
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