Back EMF with Light Bulbs

# 5J10.20

Description A large coil with iron core is in parallel with 15watts bulb, and in series with 200 watts bulb. While you closing the switch, the large bulb delayed growing, and the small bulb bright at first and dimmed later on. While you opening the switch, a flash occurs on the small bulb. All are due to Back EMF of the coil.
Location 18G, 37D