1. Sep 20, 2007

### Pris

I have a cluster of magnetic sources around a volume and I need to know the real magnetic field in a point (namely x_0) inside the volume by measurements in another point x' in the surface of the volume.

2. Sep 20, 2007

### tabchouri

hehe,

I'm getting mad about computing the magnetic field of only 1 permanent magnet.
I guess that basically, if you know the field of 1, you will know the total field (summing).
Here is a wikipedia link, in which an approximation is made, to consider 1 magnet as a solenoid. http://fr.wikipedia.org/wiki/Réluctance
Unfortunately i did not find any equivalent in English.

It says :
A permanent magnet with remnant field B, lenght l, section s, $$\mu$$ its permability, it is equivalenent to a soleoind :
- of reluctance R = l/($$\mu$$s)
- with : N.I = (l.B)/$$\mu$$, N the equivalent number of current loops, I the equivalent current
- lenght l and section s.

Imagine how is it frustrating when you need to analytically compute the force between two permanent magnets (actually, there is no viable direct computations, only based on finite element decompositions).

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Correct me if i'm wrong.