Ok so the 1st question is how can a EM create a magnetic field which I would assume spreads out at Light speed while greatly diminishing in strength with distance create the Back-emf when the Coil is turned off? Because the field was spreading out at light speed then the information that the coil is off could never reach the end of it and tell the field it needs to go back to create the Back-emf. In other words exactly how can the magnetic field reverse and casue the back-emf on the coil? I have one idea and it has to do with the magnetic field energizing space (creating virtual photons, which also would explain the strength decrease) and when the coil is shut off the field never comes back but the virtual photons collapse back to the vacuum and in doing so create a field moving back towards the coil and then creating the back-emf. So yeah, I am really confused how exactly can the magnetic field create a back-emf if it is expanding outward at light speed, which if you think about it, it has to, it can't just expand out and then just stop. and if it does then how can it ever collapse back and generate the back-emf?