In article ,
Ron Garret wrote:

There's also the conservation of energy argument. If the engine is
turning, the energy to overcome friction and compression has to come
from somewhere.

I don't think this works. In the non-spinning case, you're dissipating
all that energy into the air, and there's no real limit as to how much
that could be. Now, it would seem that the conservation-of-energy
argument gets you the right answer, but IMO not for the right reasons.

--
Mike Ash
Radio Free Earth
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