I have a microwave oven that I got at the local dump. Someone had thrown it away because it didn't work any more, the only thing wrong was the fuse inside was blown. It is a really nice one, with lots of bells and whistles, including a cooking sensor.

If I put a potato in it, and press the "Potato" button, it cooks the potato perfectly. If I put in two potatos, or four potatos, or however many, it cooks them all perfectly. Yes, it has a sensor, but how does it know how many potatos are being cooked, and how does it know when they are done?

Just what is that sensor... ummm... sensing? How does it work?

tanstaafl.