RE: E Fields From Spinning Electromagnets Magnets
Hi Fred. I googled and still disagree with the author, a self exciting homopolar generator can contain no permanent magnet material and yet when spun, will generate a current. The authors explanation that a spinning electromagnet cannot generate the E field seems just plain wrong to me based on experimental evidence. K. -Original Message- From: Frederick Sparber [mailto:[EMAIL PROTECTED] Sent: Friday, January 21, 2005 7:37 PM To: Keith Nagel; vortex-l Subject: RE: E Fields From Spinning Electromagnets Magnets Keith Nagel wrote: Hey Fred, I'm curious how they explain the functioning of the self exciting homopolar generator, N. Tesla (1891). Where are the translating current loops? Googling Guala-Valverde brings up a lot of related stuff, Keith. Eddys? Frederick K. -Original Message- From: Frederick Sparber [mailto:[EMAIL PROTECTED] Sent: Friday, January 21, 2005 6:07 PM To: vortex-l Subject: Re: E Fields From Spinning Electromagnets Magnets What if the electromagnet is wound with high turn pitch. It should translate wrt your frame like the stripes on a rotating barber pole. :-) http://www.maxwellsociety.net/PhysicsCorner/CurrentLoopPolarization/ElectroA ndPermanentMagnets.html It has been quantitatively demonstrated that the net charge density is not everywhere zero when the current loop of Sect. 1 translates along a line in its plane. Indeed a simple proof qualitatively indicates that uncharged current loops are electrically polarized when they translate. At any given moment the translating loop has an excess of positive or negative charge on one side, and an excess of negative or positive charge on the other. In brief, the translating loop has an electric dipole moment (as well as a magnetic moment), and consequently there is a nonzero electric field. This effect is only present when the loop translates. It is not present when the loop merely spins. Frederick More: http://www.maxwellsociety.net/PhysicsCorner/Electrodynamics/GualaValverde%20 Explanation.html
Re: E Fields From Spinning Electromagnets Magnets
I Googled it before going to the trouble of trying it. OTOH, a large needle on a foot of thread swung past a stationary vertical "Cow Magnet" goes into rotational oscillation above the tip of the CM. http://www.maxwellsociety.net/PhysicsCorner/CurrentLoopPolarization/ElectroAndPermanentMagnets.html "The results obtained by Guala-Valverde and others suggest a sort of rotational relativity. That is, it seems that the emf across the load depends only upon the motion of magnet and load relative to each other. (Obviously there is a nonzero emf when the magnet is at rest and the load rotates.) The problem with this conclusion is that Maxwells equations (like Newtons laws) apply only in inertial frames of reference. The contention of this article is that the experimental results are consistent with the electric polarization of translating current loops. In brief, spinning permanent magnets have spin-induced electric fields with radial components. Such radial electric fields can produce emfs across resting loads, quite as the magnetic forces produce emfs when the load moves through the B field of a resting magnet. It is worth noting another explanation suggested for the zero emf observed when magnet and load rotate in tandem. It has been theorized that the spinning magnet "drags" its B field along, so that the (also moving) load is not cutting across any B field lines. However, the emf is nonzero when the load spins within an enclosing electromagnet, regardless of whether the electromagnet spins or remains at rest. And the emf is zero when the load is at rest and the electromagnet spins! It seems somewhat ad hoc to suppose that a spinning permanent magnet drags its magnetic field along, whereas a spinning electromagnet does not." Frederick
Re: E Fields From Spinning Electromagnets Magnets
What if the electromagnet is wound with high turn pitch. It should translate wrt your frame like the stripes on a rotating "barber pole". :-) http://www.maxwellsociety.net/PhysicsCorner/CurrentLoopPolarization/ElectroAndPermanentMagnets.html "It has been quantitatively demonstrated that the net charge density is not everywhere zero when the current loop of Sect. 1 translates along a line in its plane. Indeed a simple proof qualitatively indicates that uncharged current loops are electrically polarized when they translate. At any given moment the translating loop has an excess of positive or negative charge on one "side," and an excess of negative or positive charge on the other. In brief, the translating loop has an electric dipole moment (as well as a magnetic moment), and consequently there is a nonzero electric field." "This effect is only present when the loop translates. It is not present when the loop merely spins." Frederick More: http://www.maxwellsociety.net/PhysicsCorner/Electrodynamics/GualaValverde%20Explanation.html
Re: E Fields From Spinning Electromagnets Magnets
Frederick Sparber at [EMAIL PROTECTED] wrote: What if the electromagnet is wound with high turn pitch. It should translate wrt your frame like the stripes on a rotating barber pole. :-) Would such a rotating electromagnet self-accelerate along the axis of rotation if its axis of rotation could be maintained? Harry
Re: E Fields From Spinning Electromagnets Magnets
Harry Veeder wrote: Frederick Sparber at [EMAIL PROTECTED] wrote: What if the electromagnet is wound with high turn pitch. It should translate wrt your frame like the stripes on a rotating barber pole. :-) Would such a rotating electromagnet self-accelerate along the axis of rotation if its axis of rotation could be maintained? You might have trouble keeping it on the ground. :-) BTW, there should be another field due to v^2/r acceleration. Gravity? Frederick Harry
RE: E Fields From Spinning Electromagnets Magnets
Keith Nagel wrote: Hey Fred, I'm curious how they explain the functioning of the self exciting homopolar generator, N. Tesla (1891). Where are the translating current loops? Googling Guala-Valverde brings up a lot of related stuff, Keith. Eddys? Frederick K. -Original Message- From: Frederick Sparber [mailto:[EMAIL PROTECTED] Sent: Friday, January 21, 2005 6:07 PM To: vortex-l Subject: Re: E Fields From Spinning Electromagnets Magnets What if the electromagnet is wound with high turn pitch. It should translate wrt your frame like the stripes on a rotating barber pole. :-) http://www.maxwellsociety.net/PhysicsCorner/CurrentLoopPolarization/ElectroA ndPermanentMagnets.html It has been quantitatively demonstrated that the net charge density is not everywhere zero when the current loop of Sect. 1 translates along a line in its plane. Indeed a simple proof qualitatively indicates that uncharged current loops are electrically polarized when they translate. At any given moment the translating loop has an excess of positive or negative charge on one side, and an excess of negative or positive charge on the other. In brief, the translating loop has an electric dipole moment (as well as a magnetic moment), and consequently there is a nonzero electric field. This effect is only present when the loop translates. It is not present when the loop merely spins. Frederick More: http://www.maxwellsociety.net/PhysicsCorner/Electrodynamics/GualaValverde%20 Explanation.html
Re: E Fields From Spinning Electromagnets Magnets
Frederick Sparber at [EMAIL PROTECTED] wrote: Harry Veeder wrote: Frederick Sparber at [EMAIL PROTECTED] wrote: What if the electromagnet is wound with high turn pitch. It should translate wrt your frame like the stripes on a rotating barber pole. :-) Would such a rotating electromagnet self-accelerate along the axis of rotation if its axis of rotation could be maintained? You might have trouble keeping it on the ground. :-) BTW, there should be another field due to v^2/r acceleration. Is 'r' the radius of the barber pole? Gravity? Not sure what you mean. Harry
