This question has nagged me for some time. I will appreciate your
indulgence in this.
Imagine a circular loop of wire of radis R. A uniform magnetic field is
distributed perpendicular to its surface and confined to a concentric
circle of radius r < R.
Will the change in the magnetic field strength induce a current (emf)
in the loop?
By the Faraday's law there should be an emf induced becuse of changing
flux. However, my contention is that B-field lines are not "physically"
linked to the loop. Why should changing field affect anything in the
loop?