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This is a question Amazing displays of ignorance

Sandettie Light Vessel Automatic tells us: "My dad's friend told us there's no such thing as gravity - it's just the weight of air holding us down". Tell us of times you've been floored by abject stupidity. "Whenever I read the Daily Express" is not a valid answer.

(, Thu 18 Mar 2010, 16:48)
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Yes,
In the sense that you wouldn't have to transport all the building materials to the top of a hill.

No in the sense that we use alternating current in this country so the electrons / charge / holes / current will be going in both directions.
(, Fri 19 Mar 2010, 14:49, 2 replies)
Ah, yes.
Alternating current. The nemesis of all my engineering plans!

*shakes fist*
(, Fri 19 Mar 2010, 15:19, closed)
Mwahahaha.
Got you with my AC logic
(, Fri 19 Mar 2010, 17:43, closed)
Even DC wouldnt work
You need a complete circuit, any gain on the downhill wire would be lost in the uphill wire. As for whether gravity would actually have an effect, I think it would, but vanishingly small.


quick order of magnitude calculation:

Energy change of an electron over 1m in height (at earth's surface)= mgh ~ 10^-29 J
Energy change of an electron over 1volt = qv ~ 10^-19 J

So 10 orders of magnitude different even in a fairly weak field (1 volt per metre), between the terminals of a 9 volt battery, this would come out as 10^-32 for the gravitational field and 10^-18 for the electromagnetic field

Not sure what the situation would be on a neutron star (the gravity is strong enough for the gravitational effect to trump the electrostatic effect), but have a feeling that the point where the gravity becomes strong enough the be noticeable will be the point where the matter becomes neutronium (feel free to correct me any more advanced physicsy types reading this)
(, Sun 21 Mar 2010, 19:29, closed)

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