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To: aruanan

I'm just saying that from the article, it appears to me as though these two "geniuses" have re-discovered the Right Hand rule.

Apply direct current [DC]. Get magnetic field effect.

Now, can I have my grant money for this "breakthrough"?!

36 posted on 04/03/2003 8:11:52 PM PST by Southack (Media bias means that Castro won't be punished for Cuban war crimes against Black Angolans in Africa)
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To: Southack; Gary Boldwater
I'm just saying that from the article, it appears to me as though these two "geniuses" have re-discovered the Right Hand rule.

Apply direct current [DC]. Get magnetic field effect.

Now, can I have my grant money for this "breakthrough"?!


Well, the operative words are "appear" and "to me". You're talking about a Lorentz force as observed with an electric current running along a wire, which produces a magnetic effect. They're talking about a Coulomb force as observed in a charged piece of amber--it has an electric charge, but since there is no movement of this charge, there no magnetic effect. The right-hand rule applies to the former, not to the latter.

As I said, the wording was not completely straightforward but that it supported my rather than your interpretation. I said that the right-hand rule pertained to the effect produced by an electrical current
Ampère showed that two parallel wires carrying electric currents attract and repel each other like magnets. If the currents flow in the same direction, the wires attract each other; if they flow in opposite directions, the wires repel each other. From this experiment, Ampère was able to express the right-hand rule for the direction of the force on a current in a magnetic field. He also established experimentally and quantitatively the laws of magnetic force between electric currents.
and that in this particular case the DC voltage was applied to produce an electrostatic field not to maintain an electric current. I read the actual paper and found that my interpretation of the slightly ambiguous sentence in question was, indeed, the correct one:
In all experiments, the surface-to-surface separation distance between spheres exceeded that for sparking in dry air by at least one order of magnitude. Surface-to-surface separation distances were typically larger than 5 mm. Also, the experiments were conducted in isolation from the surroundings by carefully insulating all fasteners and connectors, by utilizing a large open space, or by installing the experimental assembly in a Faraday box. Hence, current flow was negligible. We have found that our experimental model offers a particularly powerful approach to investigating electrostatic phenomena, and we have previously used similar setups to successfully calibrate the electrostatic force.1,2 The absence of electrical current and magnetic materials, natural or induced, leads us to conclude that the experimental assembly was electrostatic.
--Appl. Phys. Lett. 80, 2800 (2002), pp.2800-2801.

41 posted on 04/04/2003 8:02:22 AM PST by aruanan
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