Synchronisation
What everyone needs to know. How to synchronise 5 metronomes which are out of sync using two aluminium cans and a plank of wood.
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redazril I LIKE DRUGS!, Fri 2 May 2008, 12:24,
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Excellent
This is science in action, so how does it work then?
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Brandy_Bumwinkle, Fri 2 May 2008, 12:30,
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I'd expect
that the inertia of the swing arm movements is causing the plinth to roll slightly so that when they get to the end of their swing it gives them an extra split second of balance (like the zenith of an object that's been thrown in the air). The other arms (in the middle of their swing) then have time to catch up. As more of them sync up, the plinth moves more, as in a feedback system.
Or not.
But it's feckin' cool, and I'll bet I've got enough swing arm metronomes lying around at home. I'm trying this one out :)
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masakatsu best of all the burger meats, Fri 2 May 2008, 12:36,
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Yes, I was thinking 'roughly' the same thing :)
I only have one metronome but this makes me want more, more! Any suggestions on a variation using normal household crap laying around?
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Brandy_Bumwinkle, Fri 2 May 2008, 12:38,
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Probably
any pendulum (newtons cradles etc) would most likely have the same effect. If you make a few equal length pendulums using string and something for weights, it should work.
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masakatsu best of all the burger meats, Fri 2 May 2008, 12:42,
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A techie explanation...
In a system of linear oscillators like this one, the motion can be described by the sum of a set of "modes", each of which oscillates at a single frequency. At the beginning, the oscillators are effectively uncoupled (they'll be weakly coupled through the table, but this is too heavy to really make a difference). There are therefore 5 modes, each describing a single metronome oscillating at its own frequency. When the metronomes are put on a common board, which is capable of moving from side to side, the modes will become coupled and will describe the motion of all the metronomes in some way. Key is that the different modes lose energy at different rates due to non-linear effects (damping). The motion that you see at the end, with all the metronomes in sych is a single mode and it happens to be the one that loses energy the slowest. All the other modes therefore die away leaving only that motion being observed.
(, Wed 7 May 2008, 16:54, Share, Reply)
this is so useful!
I was just saying the other day, "I just can't sink up all these metronomes I have around the house"
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Kung_Fu_Russ ran out of amusing signatures on, Fri 2 May 2008, 13:01,
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indeed, the hell of mutilple unsynchronized metronomes defies description
:D
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discomeats This canoe, Fri 2 May 2008, 16:47,
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Another victory for Science I feel...
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evil_andy Stick stick stick stick sticky sticky stick stick, Fri 2 May 2008, 13:13,
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good stuff
I wonder if this can be used to explain how women's menstrual cycles synchronise if they live together?
(, Fri 2 May 2008, 13:36, Share, Reply)
This is why the Millenium bridge wobbled.
and he's a metrosexual.
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Carlossus, Fri 2 May 2008, 16:20,
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That's what I was thinking
I believe the term is called sympathetic vibration (though may be wrong) and also why army troops are told to break step when they cross a bridge
(, Sun 4 May 2008, 18:06, Share, Reply)
SCIENCE!
SCIENCE once again makes everything better!
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Green Spanner and his magical lack of activity, Fri 2 May 2008, 21:16,
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