RE: [MEG_builders] Re: megmania
- Hi Cyril,
> > In effect, you are suggesting that the flux of the magnet does
> > not 'really' move even though a source of flux is changing nearby. I
> > think this gets into the murky waters of what we mean when we say a
> > field 'moves'. I suppose you could construct even the field around a
> > magnet being transported from one end of the table to the other as a
> > virtual movement, if you squinted at it hard enough.
> > But the practical question is this: in my example above, if one puts
> > a wire orthogonally between the bar magnet and the two switched
> > magnets,
> Don't you mean the two switched coils?
>I think the experiment needs to be done. I'll see if I can dig up someone
> > is the induction in the wire due to the B in the wire alone,
> > or is it due to the B of the wire and the B of the magnet? This seems
> > to be a simple enough experiment. I would be very surprised if the
> > presence of the magnet did not affect the induction.
> I think you will find the induction to be the same whether the magnet is
> present or not. The magnet wll only affect the induction if it's
> magnetization changes, i.e. if the applied field (from the coils) is big
> enough to demagnetize the magnet.
to do it, and then send a report back to the list.
>The debatable word is 'source'. I don't agree that the source has to move,
> > At the very
> > least, the presence of the magnet causes the flux to pass back and
> > forth across the wire when it wouldn't otherwise.
> As you say that depends on what we mean when we say the field 'moves'.
> Motional inductance involves either the conductor moving
> relative to a fixed
> magnetic source or the magnetic source moving relative to a
> fixed conductor.
> The above experiment does not meet these criteria.
just the flux generated by that source. But let's not debate it any more.
Let's ask Nature for her opinion.