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Would a Magnetic Object Float or Levitate Over an AC Line?

08/06/2009 12:37 PM

Anyone tried this!

I would appreciate any pointers.

Thanks, Sadok

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#1

Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 1:25 PM

A think the answer can be deduced by holding a compass next to your PC's AC cord.

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#2
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 2:13 PM

Well?

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#3
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 2:31 PM

Experiment!

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#4
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 2:40 PM

I think we should Experiment with a compass as close to some high voltage trunk lines as we can get. Maybe I should go back here, and bring a compass this time.

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#5
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 3:38 PM

Yeah, just don't get too close to the line while holding the compass:

http://www.ebaumsworld.com/video/watch/80651341/

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#6
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 3:51 PM

awww.... I can't open the link from work

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#7

Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 4:15 PM
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#8
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 4:20 PM

I agree with that answer...

but...

Would any disturbance at all be present on a sensitive compass very close to high voltage lines? I have experienced some very wild sensations very near high voltage lines.

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#9
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 8:08 PM

What sort of wild sensations and how close were you? The field strength even directly underneath a high voltage line is fairly low (lower than many electrical appliances in the home), and ozone due to arching and breakdown of air needs to be in fairly high (and potentially lethal) concentrations to cause what I would consider 'wild sensations'. If you are interested, numerous previous threads on CR4 have covered this topic in depth.

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#13
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Re: Would a magnetic object float or levitate over a AC line?

08/07/2009 11:49 AM

Hair standing up, eyes burning, strange smells... that sort of thing. I was floating down a river in a rubber raft doing some fishing with a friend of mine. We both experienced the same sensations when we went under the lines coming from Bonneville dam. The "Crackle" was quite loud... enough so, it was almost like we were yelling to each other across the raft. You can read about it here, as you mentioned, it has been covered already. I have floated past there "since the initial contact of charged electromagnetic spectrum"*, and have not experienced the same sensations... I think they were having problems with something, it was quite unusual.

*Taken from a quote- "Until the 20th century, Reality was everything humans could touch, smell, see and hear. Since the Initial Publication of the charged electromagnetic spectrum, humans have learned what they can touch, smell, see, and hear is less than one millionth of reality."

I'll give a brownie to whoever can tell me where that quote can be heard. (without a google search of it)

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#10
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Re: Would a magnetic object float or levitate over a AC line?

08/06/2009 8:14 PM

Yep, me too. When I was 9, I climbed up an apple tree and touched an 1100 V line. I had wild sensations. I had no compass on me or I'd probably have broken it too when I hit the ground. For some reason, I thought a live apple tree, full of sap, would insulate me.

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#11
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Re: Would a magnetic object float or levitate over a AC line?

08/07/2009 2:15 AM

Voltage has nothing to do with it. The compass, if it were to respond, would respond to the magnetic field, which is proportional solely to current. And the compass would indeed respond to the magnetic field, if only its mass were sufficiently low that its inertia could be affected by a 50/60 Hz field. But that isn't the case with a typical compass.

Now if you had dc current, then the magnetic field would have a single polarity, and if you lined up the north pole against north, or the south pole against south, you could get the repulsion that could, if vectored properly against the Earth's gravitational field, lead to flotation. But because the field around a wire is circular with the wire penetrating the plane of the magnetic circulation at right angles, what you really need is a coil of wire, like a solenoid.

And there you have it - a solenoid is a practical example of mechanical work done by a magnetic field, due to current flowing in a wire.

emc_c

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#12
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Re: Would a magnetic object float or levitate over a AC line?

08/07/2009 3:08 AM

Hurrah for California......

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#14

Re: Would a Magnetic Object Float or Levitate Over an AC Line?

08/07/2009 12:04 PM

No. Only a 'magnetic-field-superconductive' (which in practical terms means an electrical superconductor) can levitate over a magnetic source. However, that source has to be a permanent ('magnetic DC') as opposed to an alternating magnetic source.

As concerns compasses, an AC current will generate a magnetic fields whose lines will form circles around the cross-section of the line. (Visualize it as if the AC line were perpendicular to a sheet of paper; the magnetic lines would form circles around the 'point' where the AC line intersects the paper.

A compass would attempt to line up parallel to the local magnetic lines, so it would try to orient itself within the plane of the sheet of paper, perpendicular (90 degrees) to a line drawn from the compass' location to the point where the AC line intersects the sheet.

Since the line is AC, the compass will attempt to flip over and flip back at the line's 50/60 Hz frequency. In practical terms, it'll line up in the direction to which it was closest to pointing when it arrived at the point where it's held. (Too long to explain).

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