Latest: No back torque generator.

[gravityblock]

The homopolar's power output goes up by the 4th power of increases in the rotor radius while its input power requirement goes up by the square thereof.  This is mathematical proof of Mechanical OU.

We only need to convert this Mechanical OU to Electrical OU by coupling the EMF to the voltage to have the same direction.  Another way to say this is to couple the BEMF to the EMF.  Same thing, just using different terminology or looking at it from a different perspective.

[lumen]

The homopolar's power output goes up by the 4th power of increases in the rotor radius while its input power requirement goes up by the square thereof.  This is mathematical proof of Mechanical OU.

If this was true, then why worry about the minor details like back EMF? Just build it big enough and be done!

[gravityblock]

If this was true, then why worry about the minor details like back EMF? Just build it big enough and be done!

The short answer is the BEMF or the voltage potential that is being utilized due to the more current you draw, lowers the EMF's ability to separate the charges.  This will kill the Mechanical OU properties of the device and you will never achieve Electrical OU, unless you deal with this problem.

I previously posted this while you were posting also, so you may not have read my previous post.  I will repeat it again.

Do not confuse the electro motive force (EMF) with voltage.  The EMF is the work done in order to separate the charges.  The voltage is what moves those separated charges.  The voltage is equal to the EMF but is opposite in sign or direction, thus in opposition.

The more current you draw means more voltage potential that is being utilized, thus causing the EMF to have a lower ability to separate those charges which drops your potential voltage that is available to you.

Once you couple the voltage to the EMF to have the same polarity or direction, then you no longer have a voltage potential that is in opposition to the EMF in a closed loop.  This is how to achieve electrical OU.

[BWS]

then the homopolar motor would not cause any push aginst the magnet because the lines of force are stationary in space. But we know this is not the case.

@lumen,
Can you show me an example of such a homopolar motor?

I have solid references that could be easily constructed and tested for a reactionless one piece or 2 piece unipolar/homopolar motor.  Put a magnet on a free spinning axis (unipolar style) but freely rotating.  Then make a ring of conductor the same diameter as the magnet and attach it to the magnet's rim keeping it electrically insulated from the magnet.  Then add 3 radial wires soldered to the ring conductor and going directly to a central conducting knob at the center while keeping the wires and center knob insulated from but attached to the magnet.  Space the wires at 120 degree intervals.  Now take leads from a strong battery (maybe 4 "D" cells in various arrangements) and touch one lead to the center and the other lead to the circumference.  You may be shocked but you will see the entire assembly motor without any stator.  This has historically been called the "ball bearing motor"; it is a reactionless unipolar motor.  It will work because the field is fixed in space and can not rotate, the current in the radial wires is motoring reactionlessly through the field.  This will not work well with a solid conducting disc.
-BWS

[lumen]

You may be shocked but you will see the entire assembly motor without any stator.

The rotor turns not because the field lines are fixed in space, it turns because the stator is the wire you are touching on the rim. This produces the field to keep the field from the magnet from simply sliding on the magnets face.
That is why it turns and the magnet does not.

I believe I may have found a way to prove the field is not held stationary in space and is able to freely rotate around the axis, with or without the magnet rotating.