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Re: 20 joules at 100 bps vs 4 joules at 500 bps

Original poster: "Antonio Carlos M. de Queiroz" <acmdq@xxxxxxxxxx>

Tesla list wrote:

Original poster: "Malcolm Watts" <m.j.watts@xxxxxxxxxxxx> 

Careful! Except in a trivial case noted below there is no dependency
between toroid "size" and breakout voltage. You can have a humungous
disk with enormous capacitance and  a low breakout voltage. You can
also have a tiny disk with corespondingly low capacitance and still
the same low breakout voltage. To a point the choice of ROC is
arbitrary. For a small toroid maximum breakout voltage degenrates the
terminal geometry to that of a sphere. For a giant toroid, the ROC
can be very much less than that of a sphere with same diameter as the
toroid's major diameter. You might view the thrid requirement I gave
as being somewhat equivalent to a simultaneous equation.


The table below illustrates what happens:

Exact toroid capacitances (diameters in meters, capacitances in pF, voltages in kV)
Minor d. 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 0.900
Major d.
2.000 66.248 74.141 79.188 82.952 86.002 88.612 90.936 93.059 95.030
639.43 998.45 1261.10 1470.00 1644.57 1795.52 1929.30 2050.02 2160.33

For comparison, a sphere with 2 meters of diameter would have 111 pF of
capacitance and 3000 kV of breakdown voltage. The toroids above have all
2 meters of major diameter. Divide the values by the toroid major radius
in meters to scale for other sizes.
(The values are for an isolated toroid. The presence of nearby objects
changes the values to some extent).

Antonio Carlos M. de Queiroz