# RE: TC vs Lightning

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Will -

By now you may have realized that I was thinking of the coulombs/Km
(Uman) in a lightning strike.

Thank you for the Internet site.

John Couture

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At 05:06 PM 9/28/98 -0600, you wrote:
>Original Poster: "Payne, Will E" <will.e.payne-at-lmco-dot-com>
>
>See terrestrial lightning and 'upward lightning' parameters online at
>http://www.altair-dot-org/atmoelec.htm
>Much of the terrestrial data is from Uman.
>
>Will
><snips>
>
>>   I have attempted to compare the Lightning parameters in Uman's book with
>> a typical Tesla coil using the JHCTES program. The coil is 60 KW with a 10
>> meter (32.8 ft) spark length. This coil is similar to your 55 KW coil
>> described in the TCBA News Vol 10, #2, page 14.
>>
>>                     Uman                Typical
>>                     Lightning           Tesla Coil
>>
>>   Kvolts/m          1000                316
>>   Surge Z/m         100                 2434
>>   Amps              10^4                130
>>   watts/m           10^10               4.1 x 10^7
>>   time usec         10                  10
>>   joules/m          10^5                410
>>
>>   KVs = 65 x (32.8 X 12)^.65 = 3160/10 = 316 KV/m
>>   Surge Z ohms = sqrt(ls/Cs) = sqrt(.0646/109X10^-12)
>>                = 24344/10 = 2434.4/m
>>   Amps = V/Z = 316 000/2434.4 = 130
>>   Watts = V x A = 316000 x 130 = 4.1 x 10^7/m
>>   Joules = W x t = 4.1 x 10^7 x 10^-5 = 4.1 x !0^3/10 = 410/m
>>
>>
>> >See Page 215, 'Lightning', by Uman.
>> >The typical energy in a strike is approximately 100kJ/m.
>> >Therefore a 2 mile strike would therefore dissipate about
>> >_322 MILLION_ Joules.
>> >
>>
>
>
>

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