Magic Roundabout

You're standing on the edge of a turntable, holding a heavy flywheel in
your hands.

Beginning with both axes parallel, spin that baby up..

..then rotate its axis 90° into the perpendicular plane.  This exerts a
precessional torque, which is earthed through the turntable's rigid axis,
having no effect upon its current balance of momentum..

..now brake away that counter-momentum in your hands, earthing the lot..

..you're now stood on the edge of a rotating turntable, holding a
stationary flywheel..

..flip it back to parallel and repeat the cycle..


Simplifying, assume equal MoI's for both axes (ie. 1 kg-m²-rad/s each).

Both the per-cycle input torque * angle and the resulting momentum yield
appear to be RPM-invariant; that is, the input energy cost of momentum
appears to be constant / invariant to system speed, whereas its rotational
KE is obviously squaring up..

For example, 10 purchases of 1 kg-m²-rad/s at 1 J each costs a total of 10
J (this includes dissipating half the input energy per cycle). Yet 10
kg-m²-rad/s divided by two 1 kg-m² MoI's gives them 5 rad/s each, and so
12.5 J each, 25 J total.

Using two equal MoI's, we find a 75% net loss after the first cycle, 50%
following the second cycle, 25% at the third.. we hit unity at the fourth
cycle, and 125% of unity at the fifth..  and efficiency keep rising by that
same 25% per cycle as we accumulate ever-more 'unilateral' momentum, at
fixed cost, its KE value squaring with rising velocity..


Only thought this up 24 hrs ago but barely slept since..  where am i going
wrong?  It's too simple!

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