"Don Pearce" wrote
On Sat, 01 Jan 2005 16:08:29 GMT, "Fleetie"
wrote:

Well I presume that the closest approach to the ideal capacitor is
a pair of parallel plates in a vacuum! A bit bulky for anything more
than nanofarads though!

Hey, what limits the voltage on a vacuum-plate capacitor? I should totally
know this, but above a certain voltage for a given separation, is there
any kind of breakdown?


Martin

I have a graph...

http://www.donepearce.plus.com/odds/DielectricGraph.gif

Thanks, but this doesn't mean much to me. What is "dielectric strength"?
And presumably that is per (some unit of length), is it?

I don't understand the meaning of the legend in the middle of the graph that
seems to say "olts DC / MII". Uh? I assume it should say "Volts", but what is
"MII"?

Does the (hard) vacuum break down when the electric field exceeds
X volts/metre? When that happens, what, well, happens? I can't imagine there
is a visible spark, because in the ideal case, there is no gas to glow.

Excuse my ignorance, but at least I acknowledge it!


Martin
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