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<p>Phillip Ford wrote:
<blockquote TYPE=CITE>The acceleration at the breakpoint is determined
by the relative location of the lead to the finger force. However
the force at the breakpoint is dependent on key parameters. You need
both to locate the breakpoint. I would think that Ik and rk are going
to be dependent on the key ratio. Changing rk changes the key ratio.
Changing rk also moves mass M changing the CG of the key and consequently
Ik.
<p>Phil F</blockquote>
Ok.. forget my last... going through the formulas at the appendix cleared
things up I think. Check me here will you Phil (and anyone else who
wants)...
<p>The breakpoint location is determined by a = (r/rb)g, but to find
the force needed to achieve that accelleration you need to substitute (r/rb)g
for << a >> in the equation for Force.. i.e.
<br>
<blockquote><img SRC="cid:part1.3EDE4E9D.B8CDC5BE@grieg.uib.no" height=43 width=287>
<br>becomes
<p><img SRC="cid:part2.3EDE4E9D.B8CDC5BE@grieg.uib.no" height=52 width=344>
<p>and reduces to
<p><img SRC="cid:part3.3EDE4E9D.B8CDC5BE@grieg.uib.no" height=47 width=165></blockquote>
<p><br>Which at least shows that the breakpoint force is dependant on the
key ratio... or better said dependant on the both the mass and the center
of mass of the reference key. Tho I dont see why you need to know this
to locate the breakpoint. Rather it seems that knowing the location of
the breakpoint is neccessary to find this breakpoint force.
<p>or what ?? grin.
<br>
<br>
<p>--
<br>Richard Brekne
<br>RPT, N.P.T.F.
<br>UiB, Bergen, Norway
<br><A HREF="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A>
<br><A HREF="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broadpark.no/~rbrekne/ricmain.html</A>
<br><A HREF="http://www.hf.uib.no/grieg/personer/cv_RB.html">http://www.hf.uib.no/grieg/personer/cv_RB.html</A>
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