How a microwave oven works

In short: A microwave oven heats food with electromagnetic waves of 2.45 GHz that make water molecules vibrate. The friction of the molecules creates heat.

In more detail: A magnetron produces the waves. They penetrate a few centimetres into the food and heat it from the inside, not only from the surface.

In detail

• Turntable: It evens out places with stronger and weaker field so the food warms uniformly.
• Metal: Do not use, except suitable aids. Pointed metal parts create sparks. The cavity is a Faraday cage that keeps the waves in.
• Suitable dishes: Glass, ceramic and microwave-safe plastic. No dishes with a gold rim.
• Water heating: Dry food heats poorly. Liquids can superheat and suddenly boil over.
• Safety: The door has a seal and switch. Intact appliances emit no dangerous radiation (induktionsherd-funktionsweise).