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Old 09-30-2008, 03:53 PM   #106
Erick Mead
 
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Dojo: Big Green Drum (W. Florida Aikikai)
Location: West Florida
Join Date: Jun 2005
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Re: How Long and In What Manner to Great Mastery?

Quote:
Rob Liberti wrote: View Post
With aiki skills I think there are some ways to tell a bit. The push on the chest in natural stance avoids a lot of external skills tricking you. Mike's instructor test where you push someone without physically moving (maybe I'm not describing it that well) for another example
It is how it is described -- but your instinct of a problem is right. f = ma ; a = dv/dt ; v = dx/dt

Without a change of position of some mass in a period of time there is no force. No physical movement means no acceleration means no force.

But I know what YOU mean -- the person moves in the zone of stability defined without changing the base of support. In many earlier discussions "not physically moving" was obstinately undefined by some who insisted on using that description. The nature of "base of support" should be also specified in a given case to remove that source of needless ambiguity (which you do in general terms).

Cordially,

Erick Mead
一隻狗可久里馬房但他也不是馬的.
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