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Re: [Phys-L] voltage rise/drop terminology

When I see "source" I think of a spigot with something flowing out. When I see "sink" I think of a drain with something disappearing. When teaching Gauss's law, I've said that if the net flux through a closed surface isn't zero, there must be a "source" or a "sink" for field lines. In this sense, the field lines really do appear out of one and disappear into the other. I don't think I would choose that imagery for batteries and resistors.

On 4/9/2014 3:23 PM, Bernard Cleyet wrote:
On 2014, Apr 09, , at 11:19, brian whatcott <betwys1@sbcglobal.net> wrote:

The talk of apt metaphors for an electrical circuit brings me to that great grand daddy of electrical explanatory aids, the water pump, feeding plumbing, with constrictions.
In that context, the head is the work of the pump, the flux is that of water particles not charge, and what is lost is head at a constriction, and the cumulative head lost equates to the pump's head. This model seems not to mesh well with energy source/sinks.

Brian Whatcott Altus OK

Isn’t a better analogy friction in the pipe, or better a mesh in the pipe or a water wheel. The meshet is the resistor and the water wheel is the (motor) conversion of elec. E to KE. — or energy "consumed” *** in crushing grain


bc dosen’t understand why sources and sinks are wrong****


*** please note the “….”.


**** A sink doesn’t mean the E is “lost”; just transformed or goes somewhere else, likewise the source is another transformation, e.g. "chem.” E to elec. E or KE to elec. E. No???
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