# Physics of synchonizing metronomes

**URL:** <https://boards.straightdope.com/t/physics-of-synchonizing-metronomes/448008>\
**Category:** Factual Questions\
**Created:** [May 4, 2008, 4:31pm UTC](https://boards.straightdope.com/t/physics-of-synchonizing-metronomes/448008 "2008-05-04T16:31:14Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![totoismomo](https://avatars.discourse-cdn.com/v4/letter/t/59ef9b/32.png) [@totoismomo](https://boards.straightdope.com/u/totoismomo)\
**Post date:** [May 4, 2008, 4:31pm UTC](https://boards.straightdope.com/t/physics-of-synchonizing-metronomes/448008/1 "2008-05-04T16:31:14Z")

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How would you explain this phenomenon:

[![](https://img.youtube.com/vi/W1TMZASCR-I/hqdefault.jpg "Synchronisation") ](https://www.youtube.com/watch?v=W1TMZASCR-I)

Five metronomes on a plank are started at random speeds, then the plank with the metronomes is placed on top of two pop cans so it can wiggle back and forth. After about 30 seconds, the metronomes synchronize.

It has been awhile since I’ve taken a mechanics course, but it seems to me to be some kind of resonance effect. Can this system be modeled as a coupled or driven harmonic oscillator, or something of that ilk?

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**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\
**Post date:** [May 4, 2008, 4:42pm UTC](https://boards.straightdope.com/t/physics-of-synchonizing-metronomes/448008/2 "2008-05-04T16:42:59Z")

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Done, less than a week ago: [http://boards.straightdope.com/sdmb/showthread.php?t=465973&highlight=metronome](http://boards.straightdope.com/sdmb/showthread.php?t=465973&highlight=metronome)

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**Author:** ![totoismomo](https://avatars.discourse-cdn.com/v4/letter/t/59ef9b/32.png) [@totoismomo](https://boards.straightdope.com/u/totoismomo)\
**Post date:** [May 4, 2008, 4:47pm UTC](https://boards.straightdope.com/t/physics-of-synchonizing-metronomes/448008/3 "2008-05-04T16:47:46Z")

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Oi. My bad. Mods feel free to close.

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**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\
**Post date:** [May 4, 2008, 11:30pm UTC](https://boards.straightdope.com/t/physics-of-synchonizing-metronomes/448008/4 "2008-05-04T23:30:29Z")

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To the OP … they are NOT started at random speeds. They are all started at exactly the same speed, but at random phase relative to each other. BIG difference.

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**Author:** ![Gfactor](https://avatars.discourse-cdn.com/v4/letter/g/9de053/32.png) [@Gfactor](https://boards.straightdope.com/u/Gfactor)\
**Post date:** [May 4, 2008, 11:42pm UTC](https://boards.straightdope.com/t/physics-of-synchonizing-metronomes/448008/5 "2008-05-04T23:42:45Z")

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Closed at OP’s request.

**Gfactor**  
General Questions Moderator