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Re: simplier is more difficult



Ludwik wrote:

Yes, I do know that magnetism can be presented without introducing the
N-word.

The N-word that Tom was referring to was 'nuclear' not 'north'.

And that the concept of magnetic field can also be eliminated
beacuse B can be viewed a relativistic manifestation of E. ....

This is not true in general. The only magnetic fields which can be so
eliminated are those which result from applying a Lorentz tranformation to
the purely electric field of a charge distribution that is static is *some*
inertial frame. Take the simplest case of a uniform pure B field. There is
*no* frame for which it completely vanishes. If one is to treat a particle's
(or many particles all with the exact same charge to mass ratio) behavior
when it (they) finds itself (themselves) in a uniform B field then the effect
of that B field on the system can be eliminated *to first order* (in B) by
considering the system in an appropriate uniformly rotating coordinate system
whose axis of rotation is parallel to the B field and whose rotation rate is
proportional to the B field strength. But even here there is an induced 2nd
order effect through the centrifugal effect in the rotating coordinate system
which doesn't cancel out even though the first order (in B) Lorentz force is
canceled by the Coriolis effect.

David Bowman
dbowman@gtc.georgetown.ky.us