Re: Favorite Test Questions

["Bob Sciamanda" <trebor@velocity.net>]

This is another semantic swamp!
I have always considered R=V / I to be the definition of resistance -
period.
I never refer to any statement as "Ohm's Law" (except perhaps to
discourage its utterance).

Bob Sciamanda   sciamanda@edinboro.edu
Dept of Physics   trebor@velocity.net
Edinboro Univ of PA  http://www.edinboro.edu/~sciamanda/home.html
Edinboro, PA   (814)838-7185


-----Original Message-----
From: brian whatcott <inet@intellisys.net>
To: phys-l@atlantis.uwf.edu <phys-l@atlantis.uwf.edu>
Date: Thursday, March 12, 1998 11:34 PM
Subject: Re: Favorite Test Questions


> At 12:05 3/12/98 EST, David Bowman wrote:
>
> > Light bulb filaments are made of tungsten.  Tungsten is a metal.
Metals are
> > ohmic substances.  Ohmic substances obey Ohm's law.  What it *means* to
obey
> > Ohm's law is that for a uniform current through a uniform sample of the
> > substance, the current intensity in an asymptotic steady state is
> > proportional to the electric potential difference across the sample for
a
> > wide range of current intensities and potential drops.   The
proportionality
> > constant *may* be (and almost always is to some degree) temperature-
> > dependent.  The proportionality condition is to hold for a given
*fixed*
> > temperature of the sample.
> > ...
> > David Bowman
> > dbowman@gtc.georgetown.ky.us
>
> By means of a simple four-legged syllogism and an over-constrained
> definition David here sets out to convince us that an incandescent
> filament or by the same token, another strikingly non-linear device
> like a thermistor is ohmic,  which means in MY definition that it
> would have a linear relation between voltage and current.
>
> This plainly will not do!
>
> Whatcott   Altus OK