[pooma-dev] ?

[Jeffrey D. Oldham]

Roman Krylov wrote:

> I'm sorry, I merely copied/pasted it from  
> http://www.zib.de/benger/pooma/tut-01.html#laplace
> So,... is it proposal to change that  tutorial?
> But the question persists:
>     how a metal sheet could have non-constant(spatially) electric 
> potential distribution whereas it should be constant V=const ?
> Cheers
>    Roman.

First, I apologize for my slowness in understanding the physics issues.  
I have more of a computer science than a physics background.

The purpose of tutorial 1 is to introduce using POOMA to solve Laplace's 
Equation.  The particular application of Laplace's Equation is not 
important for this tutorial.  It is just added to motivate the 
tutorial.  All the equations, iterative solutions, and programs stand 
independent of the motivation.

The tutorial begins with Laplace's Equation for a charge-free region of 
space.  (Compare with 
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/laplace.html .)   By 
the end of the first section, the tutorial introduces a charge 
distribution \Beta, modifying the iterative equation.  Then the tutorial 
demonstrates how to use POOMA to write a program simulating the 
iterative equation.

With a non-zero charge distribution /Beta, the resulting V should not be 
constant.  With a zero charge distribution, V should be constant.  
Running the POOMA program should reveal this regardless of whether one 
could prove this mathematically without the use of a program.

Does this answer your query?

>>
>> Would this text be more acceptable:
>> "... where V is, for example, the electric potential of a charge-free 
>> flat metal sheet"?
>
-- 
Jeffrey D. Oldham
oldham at codesourcery.com