Why outlets spark when unplugging - EMF & Inductors

EMF created by two ways......
1, if magnetic flux and cinductor cuts each other.
2,if magnetix flux links with coil (flux needed to be changing).
we know that magnetic field lines are closed and coil wire is closed ...how two closed things links with each other without cutting process..?????
so emf induced by two ways but  einestine said that you have only one way or noway.
so its needed to recheck faraday law....


and this is really nice video....