Why outlets spark when unplugging - EMF & Inductors

Wow. Thank you. I was thinking on how magnetic fields store energy just last week. Actually asked a physicist last week, though they couldn't answer. Diana to the rescue. :)
My intuition for inductors has always been a flywheel. In a sense, this extends perfectly to what you talked about here. It explains why current lags behind voltage, just like velocity lags behind force for a flywheel.
P.S. Capacitors, on the other hand are like springs.