What Can We Expect for ADG in a Building Like This?

[Bjarne]

Which pattern of Acceleration Due to Gravity (ADG) (approximately) shall we expect to measure inside a building like "www.katrine-lester.dk/wp-content/Domus_vista_4-Small.jpg"[/URL]
Notice the values I am asking for is primary the values caused by the buildings own gravity, not the one due to the free air gradient.

[B]Data[/B]
[LIST]
[*]Height 100 Meter
[*]Lenght 70 Meter
[*]Width 20 Meter
[*]Weiht (estimated) 40.000.000 KG
[*]30 floors
[/LIST]
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[B]1[/B]
[B]Would the ADG caused by the building itself be:[/B]
[LIST]
[*]Positive at the top for (for example + 0.100 Micro Gal)
[*]Zero, or almost zero at the Centre (14 th or 15 th and 16 th floor)
[*]Negative at the ground floor (for example minus 0.100 Micro Gal)
[/LIST]
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[B]2[/B]
Or shall we expect ADG [B]due to the buildings own gravity [/B]to be almost stable the whole way from the top to the bottom?
(for example + 0.100 Micro Gal)
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[B]3[/B]
Or shall we expect ADG [B]due to the buildings own gravity [/B] to decrease the whole way from the top to the bottom?
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[B]4[/B]
Or what shall we expect?

 

[Ich]

Consider a spherical cow in vacuum, its gravity would be close enough to that of the building. Use symmetry arguments.

 

[Bjarne]

Consider a spherical cow in vacuum, its gravity would be close enough to that of the building. Use symmetry arguments.

Shall I understand this as you think option 1 is the answer ?

 

[Ich]

Up to signs, yes.

 

[Bjarne]

Up to signs, yes.

I hope not everybody agrees, because this seems to be wrong.