In reply to Michel Jullian's message of Sat, 20 Jun 2009 10:33:26 +0200: Hi, [snip] >PPS I still don't see how a plasma can support charge on its surface, >anyone can enlighten me on this? [snip] That's the one thing that doesn't surprise me in the least. Surely, it just acts like any other conductor, with a slightly higher number of charges of one polarity relative to charges of the other polarity (e.g. slightly more electrons)? The excess charge is balanced by a shortage on the opposite plate of the capacitor. When the plasma is turned off, the excess charges attempt to reach one another via the only path available to them, which is via ground, resulting in a high voltage on the external spherical capacitor, which now has a much smaller capacitance. (However I am lead to wonder why a bolt of "lightning" doesn't simply pass through the glass envelope as the voltage rises).
Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/Project.html
