How does the wire know the magnetic flux has changed?

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SUMMARY

The discussion centers on the phenomenon of electromagnetic induction, specifically how a metal wire reacts to changes in magnetic flux. When the magnetic flux within a wire changes, it induces an electric field that drives a current. This process eliminates the need for the wire to have memory of previous states, as it only responds to the presence of the induced electric field. The key takeaway is that the induced electric field is the mechanism that prompts the wire to conduct electricity when magnetic flux changes.

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  • Familiarity with Faraday's Law of Induction
  • Knowledge of electric fields and their effects on conductors
  • Basic concepts of current flow in conductive materials
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Loniuc
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If we have a metal wire and a magnetic field "inside" it, when the flux of the magnetic field changes, then the wire "reacts" by "creating" an induced current.

After learning this law, it eventually came to my mind the question: how does the wire know that the magnetic field flux has changed? I mean, in order to note the change, the wire somehow needs to have memory: "the magnetic field flux was x one second ago, and now it's x+dx... ok, it's time to induce a current".

Inanimate objects, such as wires, i.m.o. only know what happens around them instantly, so i find very hard to understand the fact that an inanimate object can detect a change of a physical variables in two different moments.
 
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Good thinking. There must be something going on at the wire to "tell" it to induce a current. And there is. The changing magnetic field induces a surrounding electric field--it's that electric field which drives the current.
 
Ok, that makes much more sense. The change in the magnetic flux induces an electrical field, so the wire does not need to pay any attention to anything but to the existence (or not) of an electric field. This way the "memory problem" is solved: once there is an electric field (and the wire does not mind about its origin at all), the wire says: "hey, what's up? an electric field is present: ok electrons, it's time to woark: moving on...".

Thanks for your answer: it has been very clear and precise.
 

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