30 Sep
2011
30 Sep
'11
12:18 p.m.
On 29 Sep 2011 at 21:25, Tony Duell wrote:
I thought the ideal dipole had 0 separation (if you see what I mean). In
other words, the 'dipole field' is defined when the distance form the
pair of poies is much larger than their separation.
That implies of course that the field from a bar magnet is not a dipole
field , certianly not if you're close to it.
-tony
Is it? I thought a dipole field fell off as
1/R^3. Anyway, it falls
off pretty fast.
It's more complicated than that. At *near* distances, it's inverse-
square; at *far* distances, it's inverse-cube. At intermediate