Re: Spheres vs Toroids

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Paul Nicholson <paul-at-abelian.demon.co.uk> 

Hi Antonio,

You wrote:

 > I have just finished a routine that calculates exact capacitances
 > of toroids in free space.

 > Example:
 > Major diameter: 90 cm
 > Minor diameter: 30 cm
 > I get: Exact capacitance: 40.5648 pF (all the digits correct)

A better value is 40.583978.  Yours is slightly in error
because you haven't used enough decimal places for epsilon.

Multiply your answer by 8.854188/8.85 to get the correct value.
--
Paul Nicholson
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