Interesting Links Between Faraday's EM Induction and EPR

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The discussion explores the relationship between Faraday's electromagnetic induction and electron spin resonance (EPR), focusing on how a moving magnet can induce an alternating emf in a copper rod. It proposes that if the magnet's frequency matches the EPR frequency, more electrons could spin up and down, potentially increasing voltage output beyond Faraday's predictions. Participants debate the feasibility of synchronizing magnetic field transitions along the length of the rod, emphasizing the need for rapid changes in the magnetic field. Concerns are raised about the engineering challenges of achieving such synchronization in practice. The conversation highlights the importance of ensuring that theoretical concepts align with practical electrical engineering principles.
Narayanan KR
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If observed carefully, one can find similarities between a conventional generator and a EPR (electron paramagnetic resonance) machine as described below.
epr1.jpg

Imagine a magnet moving up and down so that its flux 'B' cuts the copper rod to produce an alternating emf, suppose if the movement is fast enough such that its frequency equals to the electron spin resonance frequency given by F = B x 2.8 Mhz per gauss, neglecting skin effect, more copper electrons will spin up and then spin down loosing their energy as EM radiation (as happens in Electron Paramagnetic Resonance), in that case if the length of the rod is chosen to match the wavelength of the emitted energy, then will such a condition lead to more voltage to be produced than what the faraday's law will predict ?
 
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Are copper electrons free?
 
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Baluncore said:
Are copper electrons free?
if they are not free then they might have a gyromagnetic ratio slightly different from that of a free electron, but rest of the process remains the same.
 
Narayanan KR said:
... suppose if the movement is fast enough such that its frequency equals to the electron spin resonance frequency given by F = B x 2.8 Mhz per gauss, ...
Narayanan KR said:
... in that case if the length of the rod is chosen to match the wavelength of the emitted energy, ...
That would make the λ/2 dipole resonant at one particular frequency. The B field would need to be level along the entire excited dipole.

How will you synchronise the transition from Bgreat to Bfixed, over the length of the dipole. That step edge will need to be very fast, not something a moving magnet can do.

The dipole is really a resonant folded transmission line of length λ. The step will need to propagate along the dipole from one end to the other in order to synchronise the individual electron relaxation into a coherent wave.

So what if you excited only a very short section of the dipole. Would the stable B field lines need to encircle the dipole? How would the switched field that drives the relaxation be arranged?
 
Baluncore said:
That step edge will need to be very fast, not something a moving magnet can do.
why are you worried about the engineering and design constrains instead of answering for the concept alone ? .Imagine an air cored 3 phase coil system that produces rotatory magnetic field except that the frequency is in Mhz range, now you can cut any other conductor by placing it inside the coils at ultra fast rates, the copper rod need not be half wave length but an multiple of half wave length.
 
Narayanan KR said:
why are you worried about the engineering and design constrains instead of answering for the concept alone ?
This the Electrical Engineering forum. NOT the Classical Physics forum.

The topology must be physically possible. I think you have your fields crossed.
 
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