Re: Simple pendulum on round world

From: Double-A (double-a_at_hush.com)
Date: 09/01/04 

Date: 1 Sep 2004 11:21:49 -0700

TMG <TMG@Nowhere.org> wrote in message news:<f5WdnTKdirZEc6ncRVn-gg@comcast.com>...
> Double-A wrote:
>
> > herbertglazier@webtv.net (G=EMC^2 Glazier) wrote in message news:<4472-4133A8AC-287@storefull-3175.bay.webtv.net>...
> >
> >>Two Pendulums in the same room will swing in unison. take one pendulum
> >>and change its swing in a minute it will be back in step Bert
> >
> >
> >
> > And where and by whom, pray tell, was this experiment performed?
> >
> > Citations?
> >
> > Double-A
>
> "In the same room" may (or may not) be beyond the actual effect. Google:
> coupled pendulums
>
> Read about bound and loosely bound oscillators. If you mount two
> pendulum clocks on the came wall, they will (eventually) end up
> synchronized. I don't recall the bounds of "loosely".

Thanks for the info.

Seems that Christiaan Huygens, the inventor of the pendulum clock, did
such an experiment with pendulum clocks.

But contrary to what Bert said, not just any two clocks in the same
room will swing in unison.

In the first place, the two clocks have to be identical and have a
pendulum swing rate that is very nearly the same to start with. The
two clocks have to be hung from the same support. This makes them
coupled pendulums. Huygens tried hanging one clock on the other side
of the room, and it went out of synchronization.

The pendulums don't really swing in unison. They swing 180 degrees
out of phase with each other. But they will keep the same time so
long as they are linked in this way.

Also the clocks have to be in a certain weight range. Huygens was
working with heavy clocks that he was trying to get to run aboard
ships. But if the clocks are too heavy or too light, the effect won't
work.

Also, it takes about a half an hour for the clocks to become
synchronized, not the one minute that Bert said.

Double-A

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