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Re: sparks

At 5:46 AM -0800 2/18/2001, I wrote:

>> > It's about 3 megavolts per meter.

At 05:45 PM 2/18/01 -0800, Larry Woolf wrote:
According to the EB, the field strength for electrical breakdown of air at
atmospheric pressure is 10,000 V/cm. Within thunderclouds, fields of 1000
V/cm are exceeded only over limited areas. This information is also
available in the CRC Handbook in the spark gap section.

Non-experts may be wondering whether there's an inconsistency here.

1) I stand by my assertion that for ordinary household sparks, air breaks
down at about 3 megavolts per meter.

2) 10,000 V/cm equals 1 megavolt per meter.

3) Paschen's law suggests that for larger gaps, the breakdown field will be

There is really quite a lot known about this.