Re: [Phys-L] uniform field?

[curtis osterhoudt <flutzpah@yahoo.com>]

I'd be interested in which items imply that the field strength varies. The field of an infinite plate is constant with distance, and so long as the fields from two such plates add linearly, you're assured that the parallel-plate capacitor field is of constant magnitude and direction. 


Do the items have to do with either shielding effects from free monopoles (or higher-order 'poles) between the plates, or with atomic-level fields very close to the plates?

From: Paul Lulai <plulai@stanthony.k12.mn.us>

To: "Phys-L@Phys-L.org" <Phys-L@Phys-L.org> 
> Sent: Monday, July 23, 2012 3:20 PM
> Subject: [Phys-L] uniform field?
>
> Hello.
> I need help with a fundamental concept I thought I understood, but seem to have some trouble with.
> I continually read about parallel plates with a uniform field btn the plates (assuming the distance btn plates is small in comparison to the length of the plates so one can neglect end effects).  These parallel plates often have field lines drawn in which the field lines are all equally spaced.  I've also seen some parallel plates with field vector arrows.  The arrows are equally sized and spaced and vertical (assuming horizontal plates).
> I have seen a couple of items recently that imply that the field strength varies as one moves from one plate to the other.  That disagrees with my interpretation of the word 'uniform' and with my interpretation of the field line drawings and field vector arrow drawings.  I thought the word uniform and the field lines (or arrows) all implied the field strength was constant as one moves from one plate to the next.
> Am I missing something?
>
> Thanks for any clarification.
> Have a good one.
> Paul.
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