I got the idea to draw a serpentine pattern on the unused area
of a PCB, and to test how much heat I could produce with it before
melting the tracks. On the left, you can see what it looks like. It
has a 3.6 ohms resistance.
I think this PCB could be used for "useful" applications.
Next, I decided to try something else: Boil Water
with the pcb. I filled a container with water, and inserted
the PCB in the water(see picture):
Of course, it was necessary to use a more powerful source of current than the previous one. I used my 10 Amp Variac, connected to the mains. I installed my ampmeter in the circuit, and raised the voltage progressively.
At first, I was very careful not to raise the power too quickly,
in fear of melting the PCB tracks. On the picture on the left,
there had been 5 Amps flowing in the circuit for several
minutes. The water was getting hot, but not boiling.
Finally, I raised the current up to 8 Amps. A few moments later, the water was boiling. I could hear a 60hz hum coming from the variac too...