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Re: AC electricity



Hi Tim-
I don't think anyone answered your question. You ask:
In a system where the potential energy oscillates sinusoidally,
how can any energy be delivered?
But your question only makes sense in a system where
energy is conserved. A mass hanging from an ideal spring,
oscillating in a vacuum will oscillate forever. If, however,
the mass is suspended in a bucket of molasses, the molasses heats
up and the oscillations stop.
The clue to your puzzlement is that AC only delivers
energy as long as it's connected to the wall socket. Disconnect
the circuit and the oscillations stop (except in a superconductor).
So the resistance of the circuit is the "molasses" that stops the
oscillations.
Hope this helps.
Regards,
Jack
On Wed, 17 Jan 2001, Tim O'Donnell wrote:

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.


--
While [Jane] Austen's majestic use of language is surely diminished in its
translation to English, it is hoped that the following translation conveys
at least a sense of her exquisite command of her native tongue.
Greg Nagan from "Sense and Sensibility" in
<The 5-MINUTE ILIAD and Other Classics>