Looks rather stupid, they could have killed themselves with the experiment.
I know a few ways to do such an experiment in a more safe way, but I would rather not post the details on line as if something goes wrong I do not want any legal trouble.
I recall as a student putting a neon bulb (3 cm long with no wires attached) in a cup of water. If you think put it in the microwave it lights up. Adding the water helps in two ways, it reduces the voltage on the metal surfaces of the bulb and it also acts as a dummy load for the microwave oven.
_________________
Health is a state of physical, mental and social wellbeing and not merely the absence of disease or infirmity

I am not a jigsaw, I am a free man !
Diagnosed under the DSM5 rules with autism spectrum disorder, under DSM4 psychologist said would have been AS (299.80) but I suspect that I am somewhere between 299.80 and 299.00 (Autism) under DSM4.