Induction by "flux cutting" or by "flux linking"
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:an example 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
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For those interested in a 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 of the file)
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:an example 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
— Richard P. Feynman, The Feynman Lectures on Physics
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For those interested in a 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 of the file)
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