There is a toy called shock box, where when opened it delivers a shock. It delivers a shock when opened because the circuit is broken, appareantly similarly to a how a car is started. This toy is powered by a 9 volt battery and two grouos of looped copper wires (about 1:15 ratio). You may notice i am not very knowledgable in the field of electromagnetism, so here is a video of how it is built to better explain it: https://youtu.be/0Z37iZDx63w
My question is, what is the theory behind how this works?