what motion? what velocity?

Some have claimed that only the motion of a conductor, and not the motion of
a magnet, is relevant to determining what electrical potential is induced in
a conductor by motion through a magnetic field. That suggests that a magnet
attached to a conductor, with both in motion together, will induce electric
potential in that conductor. A case used to support this is when Faraday
supposedly set up a variation of the homopolar generator which had a magnet
and conductor (disk) rotating together, and he observed a current flowing in
the electrical loop through the conductive disk. This experiment can simply
be explained as the magnetic field in rotation crossing the loop outside of
the conductive disk.

Consider the following construction of magnets. Two magnets which are slices
of a cylinder or pipe are used. The slice is perpendicular to the length of
the pipe, so the two pieces are still completely round with a hole down the
middle. The thickness is a small fraction of the radius of the hole. One of
these magnets has a larger radius than the other by about 1.2 to 1.6 times.
The length of the slice is the same for both, about the same as the average
of the twoo radii. The magnetization orientation for both has N-pole facing
outward, and S-pole facing inward. So if you set both magnets down on a flat
level table, with the open sides facing up and down, and slid one towards the
other, it would repel the other away when it got too close. Place the smaller
inside the larger, and unless you place it perfectly centered, they will be
attracted to each other.

A form is constructed of non-conductive non-ferromagnetic material (such as
plastic) to hold these magents with the smaller inside the larger without
allowing them to move. A coil is wound on this form so that it fits just
between the inner and outer magnet, going around the outside of the inner
magnet, and inside the outer magnet. The ends of this coil are are attached
to a device (perhaps a tiny light) that provides a means to detect electrical
current. This entire assembly is then placed on the end of a plastic disk
so that the open sides of the assembly with coil and two cylinder magnets is
facing in the direction around the disk. A counterweight is added to the
disk and the disk is rotated (no other magnetic field).

What we have in the above is conductors (the coil on the form) and magnets
(also on the same form) moving together as a unit. If the concept that a
conductor in motion will have electric potential inducted, even if the field
is moving with it, is true, then there should be an electric potential and
resulting current in the moving coil.

If you do get an induced current, then try moving the assembly (removed from
the disk) linearly at the same rate, such as along a track. If that works,
then try letting it simply move along with the rotation of the Earth by facing
the open ends of the assembly east and west. This is, afterall, motion. Just
because we humans do not sense it does not mean it is not their. This motion
is around 463.83 meters per second (a little over 1000 miles an hour) at the
equator. There's also the motion of the Earth around the Sun, and motion of
the solar system around the galaxy, and motion of the galaxy in the universe.
So at some angle at some times these should be adding up to a really large
velocity.

But you will find that none of these cases induces any electric potential or
current. There are many ways to say what our motion is as a we move. We are
moving relative to something else. There is no absolute motion except maybe
relative to the origin of space itself.

So what you will find is that motion of an electrical conductor in a magnetic
field has to be considered in terms of that motion relative to that field.
The motion, apparent motion, or lack thereof, of anything else around this
field that is not (significantly) affecting the field, is not relevant to
the effect of the field on the conductor crossing it. So if a conductor and
a magnetic field are crossing, it doesn't matter if the ground surface of a
planet, or the humans observing the crossing, are moving with the magnet or
moving with the conductor (or even neither).

So all the FHG derivatives I'm designing are based on the notion that the
magnetic field stays with the magnet, and that any effects of crossing a
conductor are based on motion relative between the magnet (and its field)
and the conductor.

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