Short answer — the internal “switch” is held in the on position by a magnet. Magnets become much less effective when they get hot, and while there is still water in the cooker the maximum temperature will be 100C. Once all the water boils off the temperature quickly rises — but the magnets stop being able to attract the switch when they hit around 102 - 103C or so and release the switch, turning the machine off.
So all has is a switch connected to a magnet next to the bottom of the pot. That’s it. Physics does the rest.
Most thermostats in electronics such as kettles and cookers use a bi-metallic strip inside, where the two metal layers expand at different rates.
The contacts in the switch are physically pulled apart by the strip bending when the desired temperature is reached.
https://en.m.wikipedia.org/wiki/Bimetallic_strip
Short answer — the internal “switch” is held in the on position by a magnet. Magnets become much less effective when they get hot, and while there is still water in the cooker the maximum temperature will be 100C. Once all the water boils off the temperature quickly rises — but the magnets stop being able to attract the switch when they hit around 102 - 103C or so and release the switch, turning the machine off.
So all has is a switch connected to a magnet next to the bottom of the pot. That’s it. Physics does the rest.
https://en.m.wikipedia.org/wiki/Curie_temperature I doubt they’re using magnets, especially considering how hot they have to get to lose their magnetism as you suggest.
Most thermostats in electronics such as kettles and cookers use a bi-metallic strip inside, where the two metal layers expand at different rates. The contacts in the switch are physically pulled apart by the strip bending when the desired temperature is reached. https://en.m.wikipedia.org/wiki/Bimetallic_strip
responding to someone going “i researced and did an enhire presentation on this thing” with “well wikipedia says you’re wrong” is peak internet.