Re: AC electricity

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

I personally like the analogy of the pin ball machine.  The pins represent
the fixed ions in the lattice.  The balls represent the free electrons.
When the machine is tipped one way (positive voltage across the resistor),
the balls (electrons) flow downhill and bump into the pins (dissipating
energy - heat).  When the pin ball machine is tilted the other way, the
balls flow downhill (the other way), bump into the pins and again dissipate
heat.  Note that this analogy provides for constant acceleration of the
balls between scattering centers (fixed ions) (as in reality) as well as
the slow and steady drift velocity of the free electrons.


> I know that AC delivers energy - that is obvious.
> But I still have trouble understanding how this is possible
> since half the time the potential is positve and the other
> have it is negative.  It seems they should cancel out.
> I know and can do the rms (root mean squared - although
> shouldn't it be squared mean root) for figuring out various
> quantities, but I still don't think I have a basic
> understanding on "how" it really works.


Dr. Lawrence D. Woolf; Phone: (858)-455-4475; www.sci-ed-ga.org
General Atomics; 3550 General Atomics Court; San Diego CA 92121-1194