G'morning DAVID WILLIAMS, 

 ->  DW> Put it this way: The system has gone from:

 ->  DW> ....0000M.....0000M.....0000M...0..
 ->  DW> to:
 ->  DW> <0...000M0.....000M0.....000M0.....

 -> Right on...

 ->  DW> The average distance between the balls and the magnets is
 -> less in the
 ->  DW> second arrangement, so there's a net release of energy allowing the
 ->  DW> detached ball, at the left-hand end of the second arrangement, to be
 ->  DW> propelled away at some speed.

 ->  DW> Makes sense to me.

 ->  And to me, so far;  but I'm getting hotter on the thought that
 -> the trigger's acceloration into the magnet is probably itself
 -> accelorating to create a really huge impact that sets each step
 -> off.

 DW> Sure. Each ball that collides with a magnet (3 of them) will be
 DW> accelerated as it gets there. And each ball that becomes detached from
 DW> the end of a chain (also 3 of them) will be *de*celerated as it moves
 DW> out of the magnetic field. But the accelerations will exceed the
 DW> decelerations because the magnetic fields are greater close to the
 DW> magnets than at the ends of the chains.

 DW> After a ball hits a magnet, a pressure wave will travel through the
 DW> magnet and the balls in the chain on the other side of it, until the
 DW> end ball is driven off. So the energy from the accelerations goes to
 DW> power the balls through the decelerations. It's like the well-known toy
 DW> with a set of balls hanging in a row, in contact with each other. If
 DW> one of the end balls is lifted and released, so it falls back into
 DW> contact with the others, the ball at the far end of the row is
 DW> propelled away. This other ball then falls back, sending the first one
 DW> away, and so on. The balls in between do not move much, but do conduct
 DW> the pressure wave that carries the energy from one end to the other.
 DW> The only difference in the case of the science fair exhibit is that the
 DW> arrangement of magnets causes energy to be released, so the end ball is
 DW> propelled away more rapidly than the initial impact.

 DW>                         dow
 DW> --- Platinum Xpress/Win/WINServer v3.0pr5
 DW> (1:250/514)

Happy New Year, David  ...  all the above just turned up, dated 
08/28/03 !  Deep in the bowels of Fidonet, something hiccuped...

And looking back at that issue,  I eventually found a magnet 
enthusiast who stated that the device's upper limit comes when a 
ball finally slams into the next magnet at a speed sufficient to 
shatter it's fragility - they're a bit like glass, apparently...

:-))
 
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