OK, so let's now get it clear - your math is wrong.
The building’s expected max ADG is not roughly 100microgal.
Mumble. 100 microGal isn't all that far off from 93 microGal, which is what you compute below.
Do the "spherical cow" approximation (a physics joke, Bjarne - not your bovine obsession) and treat the building as a sphere.
We will trust Bjarne's mass estimate (but we retain our doubts about it because of his displayed incompetence as below).
We will use 50 meters as the radius of the sphere (half the buiding's height). Then the ADG at the surface of this sphere approximation is:
ADG = MG/r^2 = 35.000.000 * 6.67E-11 /50^2 = 0.0000009338 m/s^2
Agreed.
Paulhoff computed this earlier, but then made a mistake converting m/s^2 to microGal.
0.0000009 m/s^2... = 0.00009 cm/s^2 (100 cm per meter)
0.00009 cm/s^2..... = 0.00009 Gal (1 Gal per cm/s^2)
0.00009 Gal............ = 0.9 milliGal (1000 milliGal per Gal)
0.00009 Gal............ = 90 microGal (100000 microGal per Gal)
The building’s expected max ADG is roughly 90 microgal.
There is no reason to lose any further precision and round this up to 100 microgal.
I may have made a mistake in this and if so I would appreciate the error being pointed out.
The two highlighted values are incorrect. The first value should be 0.09 milliGal. Since there are 1000000 microGal/Gal (not 100000), 0.09 mGal is the same as your final answer, 90 microGal.
I have been unable to reproduce the numbers presented by
MRC_Hans and by
Bjarne. I am not surprised by the latter.
What bothers me is that Strykowski and Lorenzen (
Bjarne) report the acceleration measured at the ground floor as 26.4 mGal greater than the acceleration measured at the 30th floor, with a claimed std [sic] deviation of .008 mGal. Ignoring the mass of the building, and treating the earth as a point mass at its center, that difference would be about 31.4 mGal. If the difference between 31.4 and 26.4 mGal is attributed to the building, then that 5 mGal difference is approximately 50 times the 90 microGal that we calculated as above. That's too much to attribute to error in the estimated mass of the building itself.
My best guess is that the bedrock and/or crust below Domus Vista are unusually massive, invalidating any calculation that treats the earth as a point mass at its center.
Another possibility is that my calculations are incorrect, as is suggested by my inability to reproduce
MRC_Hans's numbers. Has anyone else run into this discrepancy?