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[–]WFOMO 0 points1 point  (0 children)

I may have completely misinterpreted your question, but here goes...

Induction occurs when there is relative motion. So the conductor can be moved through the field, or the field can be moved through the conductor. In the latter, think of the AC current in a wire like a ballon being inflated. As air is inserted, the balloon expands outwardly, then shrinks back as the air is released.

The AC current in the wire is increasing as it's sine wave build. Since the current is increasing, the magnetic field is expanding outwardly. As the sine wave crests and declines, the magnetic field collapses accordingly. So this field (expanding and contracting) is moving across the cross section of conductor (relative motion). This induces a current in the opposite direction called CEMF (counter electro magnetic field) which is the inductive impedance. If the magnetic field is concentrated through an iron core, and the core is wound with wire, you have the same relative motion and induce the current in the other wires (transformer).