Re: how many volts ?

[John Mallinckrodt <ajmallinckro@CSUPomona.Edu>]

On Wed, 26 Mar 1997, Martha Takats wrote:

> I think there are two separate discussions going on here. When you use 
> values for C (or for coefficients of capacitance), you don't have to 
> think about how the charges arrange themselves on the individual 
> conductors--isn't that the whole point of using C or Cij?
> But in order to calculate C in the first place, you do need to know 
> details of how the charges distribute themselves, using the fact that 
> E=0 inside each conductor, V is constant over each, etc.

In some sense this is true, of course; these physical requirements are
what determine the charge distributions and, ultimately, the coefficients
of capacitance.  But you *can* write down a general formula for the Cij
that takes as its input *only* the geometrical information about the
conductors.

John
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