Dear List,
Sorry to dissapoint but it was always my understanding that the voltage needed to initiate sparking between rounded electrodes at STP was 30 kilovolts per centimetre. This was from a school physic book article on the subject of the induction coil. So it really does take a lot of volts to make a spark jump across even a small distance -under laboratory conditions at least- although the impressive claims made by the manufacturer of "stun guns" e.g 900 kilovolts are probable hyperbole as ionised air acts much like a zener diode and the comparatively small gap across the electrodes of the device would not support a such large voltage - 30kV per cm equals 3MV/metre with 1MV a third of this, that is 33.33cm -ever seen a stun gun with terminals nearly that far apart? I would imagine the number quoted naturally applies chiefly to low frequency a.c and d.c voltages. I will try to find references for this figure.
Jolyon
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla