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WolfKC
2003-Sep-24, 12:56 AM
Does magnetism reduce in strength per distance the same way gravity does or is it faster or slower? Anyone have the forumlas handy? For gravity isn't it something like divide by distance cubed?

The reason I'm asking is I was thinking about Nancy's (:^o) magnetic explination of how a pole shift might happen.

Musashi
2003-Sep-24, 01:24 AM
I'll check, but I think that gravity is invers to the distance squared and magnetism is invers to the distance to the fourth power.

[edited- Or I could be totally out of my head about that...]

foxd
2003-Sep-24, 03:20 AM
For monopole sources, like gravitational point sources, it is an inverse square law. For dipole sources, like magnets, it is an inverse cube law.

WolfKC
2003-Sep-24, 04:16 AM
So the chance that PX could (not that PX can actually do anything) cause a pole shift based on magnetism is extreamly remote because it would either have no magnetic effect or crash into us due to the magnetic pull. That's what I was thinking. :D
That's for nancy's theory about pole shifting due to magnetism affecting ...one side of the earth which has more iron on one side? more than another so it changes the rotation.
Gravity would affect both side evenly so it might pull the earth but wouldn't cause a poll shift.

The Bad Astronomer
2003-Sep-24, 05:15 AM
The real problem is magnetic coupling. How would it flip the Earth, exactly? It's not like the Earth's field is attached to the Earth like a rope to a piton. The Earth's field is so weak a small bar magnet can outstrip it! Huge amounts of charged particles stream through it all the time (solar wind), yet we remain unflipped.

The idea is silly, as silly as the rest of them.

WolfKC
2003-Sep-24, 01:53 PM
Agreed, not that anything I've ever seen or heard from Nancy is anything but silly...(Nancy = #-o :roll: ) but I recall something about the Atlantic rift? or whatever and I thought the "theory" was something like there's more iron closer to the surface there than elsewhere and it would pull the earth stronger there than elsewhere? Maybe I dont recall it right or misread, it's been a while.
The thing I was thinking is, even if there is more iron on the earth on one side closer to the surface.... even if the earth had a moon sized iron screw in one side... and even if PX was pure magnetized iron... and even if PX got very very close.... we're still not going to get a "pole shift” :)
Not without a collision anyway.
I supposed I should go over to the evil site and see what the actual theory is :-k ... but I dont have enough energy for that right now.

AstroRockHunter
2003-Sep-24, 04:54 PM
One thing I could never discern from Nancy's ramblings was what exactly she means by a pole shift. Does she mean that the physical poles of the Earth will move around or swap end to end? Or is it that the magnetic poles will perform the Watushi?? From my perspective, the only way that the physical poles could be radically moved would be by the physical collision of a massive body, not by the magnetic effects of same. (Note: I do not consider precession of the poles a "radical movement")

As for the magnetic poles, we know that they do move around, again at a rate slow enough as to be of no concern. Also, if I remember correctly, core samples taken from around the Atlantic rift indicate that the magnetic poles have reversed polarity several times in the past and I have heard of no research done to connect these reversals to any major geologic upheavals.

Someone, (BA maybe) please correct me if I'm wrong.

2003-Sep-24, 05:02 PM
One thing I could never discern from Nancy's ramblings was what exactly she means by a pole shift. Does she mean that the physical poles of the Earth will move around or swap end to end? Or is it that the magnetic poles will perform the Watushi?? From my perspective, the only way that the physical poles could be radically moved would be by the physical collision of a massive body, not by the magnetic effects of same. (Note: I do not consider precession of the poles a "radical movement")

As for the magnetic poles, we know that they do move around, again at a rate slow enough as to be of no concern. Also, if I remember correctly, core samples taken from around the Atlantic rift indicate that the magnetic poles have reversed polarity several times in the past and I have heard of no research done to connect these reversals to any major geologic upheavals.

Someone, (BA maybe) please correct me if I'm wrong.

She has repeatedly stated that she means a physical shift of the poles. The rotation will stop, the poles will shift, then rotation will start up again.

See (but not if you have a delicate stomach) http://www.zetatalk.com/poleshft/p21.htm