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From: David Jefferies
Date: 29 Dec 2002
Time: 15:30:16
Remote Name: 195.92.168.170
Randy,<><><> Thanks for your insight into capacitor action. When I taught electronics at Oxford I used to say "capacitors do not store charge - they store energy". The charge injected into one plate is removed from the other. Thus the currents are continuous in a circuit containing a capacitor. That is why it can be said to have an impedance. If that was not the case, you could take a 10 microFarad capacitor, hold onto a lead and touch the alternating live mains with another without getting a shock. DON'T TRY THIS!! but it would disprove your point.<><><> Considering a water analogy, a capacitor is not like a bucket or reservoir of charge. If current is represented by water flowing in a pipe, then a capacitor is an enlarged section of pipe containing a diaphragm made of rubber. The water on one side pushes the rubber sideways and displaces and equivalent amount of water from the other, which flows in the exit pipe. Capacitors do not pass direct flow, as the diaphragm stabilises when its tension just balances the water pressure. Hope this is a Happy New Year Present for you. Best wishes, <><><> David.