Here are data for moment of inertia (in kg cm^2) and FW (in g) from a 1999 S&S "L" (factory lead). Probably at most 3 digits of the MOI are of value. These data are taken by direct measurement of MOI, not by estimating, calculating, etc. Also here is a graph of the MOIs: http://home.mindspring.com/~mark.davidson/image001.gif You can see that black key MOIs are, in general, less than those for white keys. So I adjusted by multiplying the black MOIs by a constant so that black and white MOIs have the same average. This lets us see the variation a bit better. Here is that plotted with FWs (same scale - different units). The correlation is clear - if not 100%. http://home.mindspring.com/~mark.davidson/image002.gif -Mark Note MOI FW 1 29.16997558 27.3 2 23.61848338 33.8 3 31.61916331 35.3 4 31.44106266 36.1 5 23.77374439 33.6 6 31.79774992 34.7 7 23.77374439 34.0 8 31.44106266 36.6 9 31.08631919 36.2 10 22.09260054 28.0 11 29.51402814 30.9 12 23.00229884 33.7 13 29.16997558 32.3 14 23.46370832 34.2 15 29.68678335 33.5 16 33.24393696 34.5 17 23.15561605 34.6 18 31.08631919 36.1 19 24.24244311 33.8 20 32.15638098 37.9 21 31.61916331 33.5 22 24.08572425 33.9 23 30.55784863 32.0 24 23.46370832 33.0 25 31.44106266 34.2 26 23.92949134 32.2 27 31.44106266 28.3 28 31.61916331 29.4 29 22.69712228 25.6 30 30.03375161 27.9 31 23.00229884 26.7 32 29.51402814 24.5 33 26.32400971 22.5 34 21.94268498 23.9 35 28.48770185 23.2 36 21.94268498 24.5 37 31.08631919 27.3 38 23.92949134 26.0 39 31.44106266 26.2 40 31.79774992 31.1 41 23.00229884 27.6 42 30.90967639 31.2 43 23.46370832 31.2 44 31.08631919 32.2 45 27.64579357 29.3 46 22.69712228 27.6 47 27.81320332 24.8 48 21.64431172 25.1 49 28.82786681 25.2 50 22.69712228 24.9 51 31.08631919 28.7 52 30.03375161 26.1 53 23.46370832 27.5 54 30.03375161 25.2 55 21.79325537 24.2 56 29.68678335 27.3 57 29.16997558 23.9 58 20.76085471 20.2 59 29.16997558 24.0 60 22.24300205 23.9 61 29.51402814 26.1 62 21.94268498 24.8 63 28.99867822 24.7 64 26.32400971 23.7 65 20.18160237 20.0 66 25.03332665 18.8 67 18.35272975 15.2 68 26.32400971 17.5 69 25.35308171 17.6 70 18.76748803 16.9 71 25.03332665 17.1 72 17.1346962 11.0 73 24.55733868 16.8 74 18.76748803 15.7 75 24.39964792 16.4 76 23.30941921 12.4 77 17.40196867 11.1 78 23.46370832 13.9 79 17.40196867 11.4 80 20.90688267 9.9 81 20.18160237 7.6 82 14.94136112 6.7 83 20.18160237 7.7 84 14.81671495 6.1 85 20.6153127 6.4 86 14.94136112 6.6 87 20.76085471 6.3 88 22.39388951 6.5
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