Idea: Homopolar motor with multiwinding coils

[Low-Q]

Im not sure I buy the electric field of a magnet or that it is how induction works. Im finding the flux cutting more logical as time passes. Like a toroid transformer with a pri on one side and a sec on the other side, I believe that the field developed by the pri expands across the hole of the toroid core to 'cut' the sec.  Measure 1 wire through the hole and compare to any other position around the core. Its all or mostly happening in the hole. So during changing currents such as AC input, there is a lot of action in the hole and not just fields stuck in the core itself.

If we look at the different ways the homopolar copper disk and ring magnet produce current and other ways do not, this should be telling of magnetic fields.

If we spin the copper disk and the ring mag is stationary, we get current in the copper disk.

If we spin just the ring magnet, we get no current in the copper disk.

Now if we spin the ring magnet and the copper disk, we get current from the copper disk.

This tells us that the field from the magnet is stationary when the ring magnet spins, as in spinning the magnet on axis does not drag the flux in the spin. There may be some field strength imperfections of the magnet that may give the idea that the field is being dragged, but it is just that, an imperfect magnet.

Spin just the magnet and the flux is stationary and is not cutting the copper to induce current. Spin the magnet with the copper disk or leave the mag stationary and only spin the disk, then yes we get current either way..

The interesting thing would be is if the mag and copper disk spin together, would there be a drag on the spin if the disk current is loaded?   If there is, what is it dragging against?

Mags

The magnetic field in a toroid transformer is not only in the core, but also outside the circumference and inside the hole.
As the AC flows through the windings, this field gradient expands and contracts through the windings. The iron core only helps keeping up the inductance for the transformer to not draw too much current.


The homopolar motor works pretty much like a railgun, except with a railgun you do not need magnets. But the railgun needs brushes to connect the projectile to the two conducting tracks.
With a railgun, the magnetic field is always propelling the projectile in one direction, but if you connect the powersupply in the middle of the track, and place the projectile in the middle, the projectile might stands still, except if you place the projectile slightly on one or the other side of the connected powersupply - the projectile is flying away one or the other direction.


With a homopolar motor, there are no end of the track since it is circular, so without the permanentmagnet, it cant determine which direction it will rotate. So a permanent magnetic field is necessary to determine the direction. The conductor in a homopolar motor is therefor propelled very similar to a railgun.


In both concepts it is impossible to introduce  multiple windings, because it is not the magnetic field in the winding itself that starts the propulsion, but the repelling forces between the wire itself and the disc. The Lorentz force.


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