---------------------- multipart/alternative attachment Richard Brekne wrote: >> Comparing the force required to push the key down slowly (less than >> the acceleration due to gravity) with no lead and with the lead will >> reveal that less finger force is required when you have lead in the >> front portion of the key. Comparing no lead and lead when applying a >> forte blow (much greater acceleration than that due to gravity), it >> will require more force applied to the key with the lead to >> accelerate the key at the same rate as with no lead. Decoupling the >> lead in the diagram is simply to help visualize this phenomena. > > > Answer me this then.... a see-saw with 5 grams of mass 1 meter from > the fulcrum on each side, and another with 500 grams of mass 1 meter > on each side of the fulcrum. Same scenerio.... less then 980/sec^2 > acceleration and then greater then that. While I'm pondering that on > my evening walk... I am sure ya'll will ponsk out an answer for me :) Yes... I would like this answered. You see the thing is, this whole diagram pulls the lead in the front of the key way out of its relevant perspective. The key is to begin with balanced such that there is more mass on the capstan side then there is on the front side. That mass back there also has to be moved.... accelerated as it were. If that mass is left alone and we decrease key front mass, then it will take more finger energy at the front of the key to move it regardless of gravity's affect. So the illustration is misleading me thinks. If we on the other hand change both the mass at the capstan and the mass in the front of the key to keep the same or similar balance weights (as we usually do), then an increase in both will also mean more finger energy is needed to get the thing moving (acceleration), again regardless of gravity. So either way the illustration seems misleading. If you first are going to look at how gravity kicks in and out of all this, then you have to look on both sides of the balance situation ... or what ? If the front gets some added help from gravity for a bit, well the back gets the opposite effect... no ?? cheers -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/b3/ea/81/53/attachment.htm ---------------------- multipart/alternative attachment--
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