Re: Ohm's Law

[Larry Woolf <larry.woolf@GAT.COM>]

If devices or materials are non-ohmic, it is customary to provide a graph of
current vs voltage in the range of interest.

For non-ohmic materials, delta V/delta I is also known as the differential
resistance.

A material is considered to be non-ohmic if the I-V curve is non-linear, all
other variables being held constant.

Larry Woolf; General Atomics; 3550 General Atomics Court, San Diego, CA
92121; Phone:858-455-4475; FAX:858-455-4268; http://www.sci-ed-ga.org

-----Original Message-----
From:  Chuck Britton
Sent: Friday, February 08, 2002 2:11 PM
Typical EE's DO in fact speak often of the DYNAMIC resistance of
non-linear (i.e. interesting) devices. The dynamic resistance is
defined to be delta V / delta i at a specific 'load point'.

At  3:08 PM -0500  on  2/8/02,  Michael Edmiston   wrote
> (4) This is the one I quibble with the most.  If a device is non-ohmic,
then
> I would not even say it has a resistance.  I don't think the typical
> electrical engineer would speak of an operating diode or transistor as
> having a resistance even though it has a potential difference across it and
> a current through it.
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