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Re: angular momentum transfer?

The experiment as described to me was that this was something shown to
senior high or first year university students. During spin-up (or
spin-down) of a lead (Pb) wheel, a second stationary wheel would slowly
start rotating, but in the opposite direction of the powered wheel. Both
wheels were reportedly on the same rigidly mounted axle. If I attempt it I
must use a Pb rim according to what I heard. No reference to RPMs or wheel
weights or diameters were given. Searching the Internet the only device
even similar seems to be a reference to a letter submitted to IEEE by a
Harvey Morgan.

Harvey Morgan paper accepted and published in IEEE Aerospace and Electronic
Systems (AES) of January 1998, pages 5 to 10, "Now we can explore the

In the Internet library archives I came across another reference to that
same paper. Both writers are speculating and assuming it's some kind of
field phenomena, which means the axles were in-line yet probably physically

As fascinating as that Morgan submission to IEEE was, although close,
that's not exactly what I was trying to locate. No one here recalls ever
being shown two wheels one powered the other reverse-responding from
stand-still on the same rigid axle? Everyone here agrees that both the axle
coupled wheel story I was told and the non-coupled Harvey Morgan submission
to IEEE are probably both urban legends. Yes? That assurance might save me
a lot of trouble. Thanks.


At 06:40 PM 8/27/2004, you wrote:
Coupled oscillators exchange energy, but for a balanced spinning wheel
there is no mechanism to counter rotate the other wheel , I don't think.
However, a wheel with an offcenter weight, so that the wheel will
swing like a pendulum, should couple the swing to the other wheel
via spindle nutations, I would think.

Brian W

At 04:11 PM 8/27/2004, you wrote:
>Hi Sam,
>Great. I have a tap & die set here. Ok, I can proceed according to those
>instructions, thanks very much.
>BTW, is there a reference? What is the demo called? Are there any pictures?
>And what is the physics teacher's explanation, I mean why does it happen?
>Anyone? Thanks very much.
> At 04:23 PM 8/27/2004, you wrote:
> >Join two bicycle wheels along the same axle. I machined a connector
> >from aluminum. You'll need to buy a special tap for the axle threads - I
> >don't remember the size but you can measure your axle. The tap is
> >readily available from shop catalogs like MSC. You don't need to add
> >lead to the rim.
> >
> >Sam
> >
> >Colin Quinney wrote:
> >
> > >Hello.
> > >
> > >I joined yesterday. I am searching for some information. I am a
fairly new
> > >student of physics, now retired, and I am presently searching for a
> > >reference to a classroom demo that shows two wheels on a short axle,
> > >one wheel with lead (Pb) rim is spun up- and another wheel close by (on
> > >the same axle) responds to the momentum change of the first wheel with a
> > >small reverse rotation. I wish to replicate this so that I may study the
> > >phenomena. Neither my text books nor Google however give a reference or
> > >shows this demonstration. I'm confident however that a demo of this
> sort is
> > >out there somewhere since a retired physics professor originally told me
> > >about it. If anyone could please advise or give a science book
> reference or
> > >to a correct Google search term, I would be most appreciative. Thanks.
> > >
> > >Best Regards,
> > >Colin
> > >
> > >

Brian Whatcott Altus OK Eureka!