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Huygens' Clock Puzzle Solved
PhotoGuy writes "Okay, I haven't heard of this puzzle either until now, but it sounds like a fascinating phenomenon. According to this article:Huygens had two clocks side by side and he found that even when they began out of sync, they soon got into a rhythm where the pendulum on one moved as if it were a mirror image of the other.The article is pretty light on the explanation, noting only the conditions required (small relative mass of the pendulums [pendula?], relatively close speed of the clocks), and not really addressing the physics behind it.
" There's a great site at Georgia Tech that explains the puzzle in more detail.
I'm interested to see if this may lead to a better understanding of how harmonics works with relation to high-rise buildings. Particularly in earthquake country. (see this)
We've got buildings that can withstand strong quakes -- but not necessarily those of long duration. I'll bet a shiny new penny that this reseach may be insightful in this field.
-jhon
Not so. The three would each be off by 1/3 of a period.
Just like three phase power... three sine waves 120 degrees apart. Sum them and you have a constant 0.
I've no idea if that would actually happen in that setup, but my guess would be that yes, they would cancel each other out in total antiphase this way.
isn't this analogous to the playground swingset, where when you swing on one, the other moves, due to the vibrations being transmitted thru the swing overhang?
uh news?
i noticed that shit when i was like 4.
That has nothing to do with pendulums.
It seems to me that it's very much the same thing. In both cases you have oscillators with periods very similar to each other linked by very weak coupling.
The interesting things are that this coupling, even if it's very weak, can influence the system and bring up synchronization and that depending on what's up you can have locking on an in-phase state or an anti-phase state.
The same kind of things happens in a lot of other systems, like for example the coupled lasers I have here.... (in-phase and anti-phase in this case appear depending on the sign of the coupling coefficient).
Not really, Although you have a valid point, the article specifically states that the effect only worked on smaller weighted pendulums - larger ones would have a stronger gravitational effect. On top of this, if both pendulums were started in the same direction, then they would not be moving away from each other and thus the gravitational effects on each other would be unchanging. Thus gravitational effect would have no bearing at all. In the article at Science News (http://www.sciencenews.org/20001007/mathtrek.asp) they specifically mention that the pendulums were started in opposite directions, and also in the same direction.