Re: [Phys-L] positive sign in Ohm's law ... or not

[Dr Keith S Taber <kst24@cam.ac.uk>]

Sorry, but R = V/I defines resistance. Ohm's law says that V and I are 
directly proportional (that is, R is fixed) in metallic conductors 
subject to certain conditions. V=IR does not (sensibly) represent Ohm's 
law.

Keith



On 03/04/2014 22:09, John Denker wrote:
> One more thing:
>
> In conjunction with Lenz's law, there has been a fair bit of
> discussion about the "positive sign in Ohm's law".
>
> ... If you write
> the law as V=IR
...

--


Dr. Keith S. Taber
Chair: Science, Technology & Mathematics Education Academic Group
University Reader in Science Education
University of Cambridge Faculty of Education


Editor: Chemistry Education Research and Practice
(Published by the Royal Society of Chemistry)
http://www.rsc.org/publishing/journals/rp/about.asp


Book Reviews Editor: Studies in Science Education
http://www.tandf.co.uk/journals/titles/03057267.asp



http://www.educ.cam.ac.uk/staff/taber.html

https://camtools.cam.ac.uk/access/wiki/site/~kst24/index.html



Science Education Centre
University of Cambridge Faculty of Education
184 Hills Road
Cambridge CB2 8PQ
United Kingdom


ECLIPSE -
Exploring Conceptual Learning, Integration and Progression
in Science Education
https://camtools.cam.ac.uk/wiki/eclipse/Eclipse.html