When I started to study the electromagnetic induction, I understood by the Faraday-Lenz law that everytime there is a change of the magnetic flux through a turn whose surface is S, the turn itself will experience an emf equal to the opposite of the change of the magnetic flux in the unit of time. By the way, I am confused because here the concept of electric potential makes no sense (the electric field is not conservative) but if we consider a turn in a variable magnetic field, it can be seen as a loop with a battery and a resistance connected in parallel. I am not sure why this is possible because the battery creates a diffetence of potential between two points but here the difference of potential makes no sense.
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If you have a closed loop of wire in a changing magnetic field, the changing flux will induce a current in the loop. The emf determines the work done (in joules/coulomb) to move a unit of charge around the loop against the resistance of the wire. There will be no measurable voltage drop between any two points in the loop since the energy is dissipated from point to point in the resistance. If you cut the loop at any point, then the current will stop and the emf will appear as a voltage drop across the gap. If you connect a battery across a loop, it will create a changing flux of it own, and the “back emf” will determine how fast the current approaches the limit determined by the resistance of the battery and loop.
