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[Fwd: simple magnets question]



Roger Haar wrote:

Sorry,
I re-install of my mail utility left it in an odd mode.

Leigh Palmer wrote:...and to think I used to object to people who intercalated
TeX!

************************
HI,
I will take a swing at rephrasing this question. First, let me modify the
question slightly. I am thinking of it in terms of a horseshoe magnet that is
spinning about its symmetry axis. The magnetic field lines are basically confined
to the region between the poles or inside the magnet itself/ the electron is
sitting on the axis between the center of the poles.

A
X
I
S
|
M | M
M | M
M | M
M | M
N e S
|

As the magnet spins the magnitude of B is constant, but its direction changes, in
cylindrical
coordinates:
partial_d B / partial_d t is in the phi direction.
and
curl of E being in the phi direction.

Possibly more useful: In rectangular coordinates with the axis being z, and at
the moment
that B is along y then at the electron ( point (0,0,0):
partial_d B / partial_d t is in the x direction.
and
curl of E being in the x direction.

That is the E-field lines form a loop around the x axis. From what I can figure,
the electron
does not respond to this field, but I am not sure.

Thanks
Roger Haar U of AZ

************************************************
William Beaty wrote:

On Wed, 23 Jun 1999, John Mallinckrodt wrote:

> On Wed, 23 Jun 1999, William Beaty wrote:
> > ... when an electron moves parallel to the face of a very large, flat
> > magnet where the direction of the field is perpendicular to the face.
> > The electron should "see" the relative motion of the field, and so be
> > deflected perpendicular to this motion and parallel to the magnet face,
> > resulting in a circular path.
>
> All an electron ever "sees" (in the sense of reacting to by virtue of its
> charge) are electric fields. It is the observer who may see an electron
> "moving through" and reacting to a magnetic field.

Yes, so the question becomes: "does an axially-spinning disk magnet create
a motional e-field which can attract/repel a stationary charged particle?"

CUT