Why outlets spark when unplugging - EMF & Inductors

When turning "ON" the giant current-carrying inductor,  You should get just the opposite of the giant spark, as "THE TENDENSITY OF CURRENT TO FLOW WORKS BOTH WAYS!"  When turned ON, it does NOT want to start flowing so you should see no spark if you have a good sturdy switch and connect hard and fast, not much wear.  That switch was a bit, not to sound insulting, flimsy.  If the switch is nice and sturdy, the sparks still appear when it is opened properly, the sparks show up, and things get all corroded and yucky-burnt.
a good example was at about timestamp 1:11 but the camera got switched about one frame too fast to NOT see the sparks when closing the switch!!!
The water analogy is GREAT for both of these inertial effects.
PS:
That is one great shrunken dime.  Do you know the capacitor (C, V) ratings, and the wire size and # of turns used?  I want to make some,  I can't even see any radial stress lines, or signs of detail (writing) inward shifting.  It really looks flat too!