use of "current" in Vol I, Chp 13, Capacitance

Thread Starter

swaller

Joined Jan 19, 2007
2
First, thanks for a great site and a fantastic resource!
Very basic question: in Vol. I, chp 13, I got confused when I read:
When voltage across a capacitor is increased or decreased, the capacitor "resists" the change by drawing current from or supplying current to the source of the voltage change, in opposition to the change.
I understood that "current" exists when there is a circuit. With a capacitor, as in the circuit diagram immediately preceding the sentence just quoted, there seems to be no circuit (unless the electric field counts as a conductor). So I don't understand how the capacitor can "draw current".
Or is it that current exists (for however short a time) whenever there is a difference of voltage across a length of conductor? i.e. a "circuit" doesn't have to be "round", or start and finish at the same point??
Any help in getting my head around this would be greatly appreciated!
Steve
 

Thread Starter

swaller

Joined Jan 19, 2007
2
Thank you, thingmaker. I'll reread the first few sections of Vol I and see if I can get a clearer idea of what "circuit" means.
 
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