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<p>Phillip Ford wrote:
<blockquote TYPE=CITE>>Where r =10 cm; rb = 5 cm; rk = 2.5 cm; m
= 30 grams and M = 140 grams.
<br>>(just accept these as working values)
<br>></blockquote>
<blockquote TYPE=CITE>
<br>Ric,
<p>This all looks OK except that you need to be consistent in your units.
For your distance measurements you're using cm, but for g you are using
m/s^2. You need to be using 980 cm/s^2 or change your distance measurements
to meters.
<p>Phil F
<br> </blockquote>
Grin.. I DID that didnt I ?? so what... this changes things to.... :)
<br>
<blockquote>That gives if so (r/rb)g = 19.6 ms^2 which should then
be the breakpoint
<br>acceleration for this example.
<p>Fbr then is (140 * .025 + I<sub>k </sub>/ .05 )( 9.8 / .1), and if Ik
can be understood to
<br>be Mr<sub>k</sub><sup>2</sup> then thats 140 * .025<sup>2</sup> = which
gives .0875
<p>(140 * .025 + .0875 / .05) * 98 = 514.5 grams of force needed to reach
the breakpoint acceleration.</blockquote>
btw... droped a 500 gram weight on a few keys today to sort of assess the
blow strength. I let the 500 grams start about 1 cm above the key... and
this yeilded what I would call a <i>mp - m</i> level of play.
<p>So... assuming the above is more or less correct... our breakpoints
are limited to fairly soft levels of play.
<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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