In reply to Harry Veeder's message of Thu, 15 Oct 2009 23:59:56 -0400: Hi, [snip]
Well Harry, I've done my best. I have nothing more to contribute. > > >----- Original Message ----- >From: [email protected] >Date: Tuesday, October 13, 2009 5:28 pm >Subject: Re: correction /Re: [Vo]:The Electric Field Outside a >Stationary Resistive Wire Carrying a Constant Current > >> In reply to Harry Veeder's message of Mon, 12 Oct 2009 02:35:43 - >> 0400:Hi, >> >Ok, I guess it is necessary to distinguish between a capacitor, a >> >battery and an EMF. Both a battery and a capacitor can produce a >> >current for a _limited_ period of time, whereas an EMF can produce a >> >current for an _unlimited_ period of time. >> >> There ain't no sich animal. Nothing runs forever. The universe is a >> big battery, >> and it's running down. > >Who can say for sure? >Who wants to say for sure? >IMO, the application of some currently recognized physical principles >governing machines to the entire universe is like painting oneself into >a (spiritual) corner. Newton was aware his clockwork universe would run down >so he allowed God to periodically intervene in his clockwork universe to >wind things up. On a deeper level he believed creation was more than >what could be explained by his axioms/laws. > >> You can only maintain an EMF at a "constant" >> level, when >> current is flowing in a resistive circuit, by supplying energy >> IOW you have to >> "pump" the electrons from the low voltage side back to the high >> voltage side. >> This is usually done with a changing magnetic field (i.e. a >> generator or >> dynamo), which once again introduces a step in the voltage going >> around the >> circuit. You can picture the voltage at each point as single >> rotation of a helix >> with a vertical axis with the begin and end points joined by a >> straight vertical >> line. That vertical line is where the energy is added. Energy is >> lost to >> resistance as the current runs around the helix. > >I agree. >The point I have been trying to make is that an EMF is technically not >same thing as electrical field. They are different animals. > >> > >> >With that in mind, let me refine the question. Can a current which >> runs>indefinitely (and does not occur in a superconductor) be >> explained>consistently only with the concept of an electric field? >> [snip] >> Regards, >> >> Robin van Spaandonk >> >> http://rvanspaa.freehostia.com/Project.html >> > > >Harry Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/Project.html
