Is Faraday´s Induction Law correct?

[hanon]

I want to open a dicussion about the universal validity of the Faraday Law of Induction. It seems that there are two kind of induction and we should clarify if both are identical or both are different phenomena.

A) Induction by flux cutting the induced wire: this induction is done in current generators and the flux lines must cut the wire. It requires relative movement (at speed v) between the field and the wire

                 E = B · v · Length

B)Induction by flux linking two coils: this induction is done in transformers. The flux lines do not need to cut the wire. It is just need a variable magnetic field

                E = -N · S · dB/dt



Richard Feynman (Nobel prize winner) about the electromagnetic induction:

    "So the "flux rule" that the emf in a circuit is equal to the rate of change of the magnetic flux through the circuit applies whether the flux changes because the field changes or because the circuit moves (or both) ...

    Yet in our explanation of the rule we have used two completely distinct laws for the two cases  E = v x B  for "circuit moves" and  E = -S· dB/dt  for "field changes".

    We know of no other place in physics where such a simple and accurate general principle requires for its real understanding an analysis in terms of two different phenomena.

...

The "flux rule" does not work in this case [note: for an example explained in the original text]. It must be applied to circuits in which the material of the circuit remains the same. When the material of the circuit is changing, we must return to the basic laws. The correct physics is always given by the two basic laws

F = q · ( E + v · B )
rot E = - dB/dt                              "

            — Richard P. Feynman, The Feynman Lectures on Physics  .
Source: http://en.wikipedia.org/wiki/Faraday_paradox#Inapplicability_of_Faraday.27s_law

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For those interested in an interesting fact about the Induction Law here I link a file which explains that two different formulations seem to exist for the same phenomenon : one, the Faraday Unipolar generator: E = (v · B) , other the Maxwell 2nd Law : rot E = -dB/dt, which are two different formulations for the same law !!! "Faraday or Maxwell" by Meyl (read page 5 and next) http://www.k-meyl.de/go/Primaerliteratur/Faraday-or-Maxwell.pdf

Another great paper by Cohn: http://www.hyiq.org/Downloads/George%20I.%20Cohn%20-%20Electromagnetic%20Induction.pdf

"THE FLUX LINKING LAW, E = -dB/dt, AND THE FLUX CUTTING LAW , E = B·l·v, OFTEN ERRONEOUSLY ARE CONSIDERED AS MERELY DIFFERENT WAYS OF EXPRESSING THE SAME PHENOMENA. THIS ARTICLE ATTEMPTS TO DISPEL THE CONFUSION SURROUNDING THE SUBJECT OF ELECTROMAGNETIC INDUCTION"  (Cohn, 1949)

[MarkE]

Nothing that you have said challenges Faraday's Law of Induction.  You have pointed out the distinction between Faraday's Law that is expressed in terms of physical motion, with the more general form that is expressed in terms of changing flux density.  Faraday's Law is a subset of the general form.

[forest]

Nothing that you have said challenges Faraday's Law of Induction.  You have pointed out the distinction between Faraday's Law that is expressed in terms of physical motion, with the more general form that is expressed in terms of changing flux density.  Faraday's Law is a subset of the general form.

Where is that "general form" ? All I see is two different equations, one working when flux is changing and one when flux is stable.

[MarkE]

Where is that "general form" ? All I see is two different equations, one working when flux is changing and one when flux is stable.

Both equations boil down to induced EMF being the result of and proportional to the cross product of the conductor length and the time rate of change of flux density perpendicular to the conductor.

[hanon]

As many of you know there are occasion where the Faraday´s induction Law (E = - S · dB/dt) cannot be applied. There are some paradoxes where the calculation with E = -S · dB/dt  cannot be done, so it is not a general equation . Therefore it seems that induction is derived from two different phenomena: FLUX LINKING and FLUX CUTTING, each one with one different equation. This paradoxes come from Faraday´s  time. ( Faraday Paradox: http://en.wikipedia.org/wiki/Faraday_paradox   )

As all universal laws in nature, it would be great to find an common underlining principle which could explain both phenomena

Here I link some very interesting documents:

"Electromagnetic induction without magnetic field"   (Hooper-Monstein effect)  ( see pdf below )  http://jnaudin.free.fr/html/hoopmnst.htm

      This comes from the work from Hooper ( http://www.rexresearch.com/hooper/horizon.htm ), Monstein ( http://www.rexresearch.com/monstein/monstein.htm )  and Crane ( see pictures below , http://www.rqm.ch/Central%20Oscillator%20and%20SpaceQuantaMedium.pdf ). Crane postulate attraction a repulsion of poles as rotating fluid-like stream in the same or opposite directions. Again other scientist proposing vortex-like foundations for this behavior, also stated by Howard Johnson, Roy Davis – Crawl and others...

"Faraday Final Riddle: Does the field rotates with the magnet?  ( see pdf below )