Microwaves generate very short, high frequency radio waves that are just right for being absorbed by water, fat and sugar molecules within organic matter. This energy causes them to vibrate at very high speeds, which in turn generates heat that cooks the food. However, the molecules of metal objects heat up quickly and with nowhere to go, these ignite quickly. Some metals depending on their shape and smoothness will reflect the microwaves instead of absorbing them. These will be reflected to the walls of the microwave, which will reflect them back. This continues until one of the transmitters gets overheated and becomes damaged.
Why should we microwave food in glass utensils, and not in metal ones?
