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Old 12-13-2012, 08:35 AM   #147
charliefedererer
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This is a trebuchet catapult.



This is a schematic of a trebuchet in action:



Note how limp it keeps it's "wrist".
[Really no surprise - there is no "muscle" to keep the wrist in any one position - it is after all just a rope!]

But man, oh man!

Just look at that great "wrist" action - seen even better in this simulation:






Sort of reminds me of the great "wrist action" in a tennis serve strobe photo:






The above doesn't conclusively "prove" the "wrist snap" in tennis is a passive motion, resulting from a "loose wrist" being allowed to move quickly through its natural range of motion because of forces being generated much more proximally.

But it does get one thinking ...
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