Re: comprehending electric/magnetic interactions

[Joe Heafner <heafnerj@VNET.NET>]

On Tuesday, Jul 1, 2003, at 19:40 US/Eastern, Roger Haar wrote:

>   If you look in most text books one finds a
> discussion of the torque on a magnetic dipole but
> nothing about the force between two magnets.  Why,
> because this second situation potentially ugly,
> because it involve how quickly the field spreads
> out and weakens.

Chabay and Sherwood's _Matter & Interactions Vol. 2_ is the only text I
know of that treats the force between two magnets. The treatment is
based on a dipole approximation and works very well. Students have a
small, but relatively powerful, bar magnet that comes in the text's
experiment kit. They first determine the dipole field's dependence on
distance and then the magnet's dipole moment.

I learned quite a bit form doing these activities.

Cheers,
Joe Heafner