RE: How many volts ?

[John Mallinckrodt <ajmallinckro@CSUPomona.Edu>]

On Tue, 25 Mar 1997, LUDWIK KOWALSKI wrote:

>       The plates are NOT infinitely large in my problem. I know that d=1 cm 
>       is already quite small for plates whose diameters are 100 cm. Yes,
>       fringe effect becomes negligible when |Q1|=|Q2|. How do you know it
>       is also negligible when one charge is ten times larger than another?

The fringe effect between the plates of a parallel plate capacitor is
negligible precisely *because* the plates are large relative to their
spacing.  It has nothing whatsoever to do with the amount of charge on
either plate.  This is because the plates are equipotentials and the field
near the surface of the plates must, therefore, be perpendicular to the
plates.

John
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