HowYourMicrowaveOvenWorks

Mode mixer

Magnetron

Oven cavity

Glass turntable

Microwave ovens are safe. Microwave energy is not hot. It causes food to make its own heat, and it’s this heat that cooks the food.

Microwaves are like TV waves or light waves. You can’t see them, but you can see what they do.

A magnetron in the microwave oven produces microwaves. The microwaves move into the oven where they are scattered or stirred by a mode mixer (like a fan). Microwaves bounce off metal oven walls and are absorbed by food.

The glass turntable of your microwave oven lets microwaves through. Then they bounce off a metal floor, back through the glass turntable and are absorbed by the food.

Metal flbor

Microwaves pass through glass, paper and most plastics without heating them so food absorbs the energy. Microwaves bounce off metal pans so food does not absorb the energy.

Microwaves may not reach the center of a roast. The heat around the outside is what cooks the roast all the way through. This is one of the reasons for letting some foods (roasts, baked potatoes) stand for a while after cooking, or for stirring some foods during the cooking time.

The microwaves disturb water molecules in the food. As the molecules bounce around bumping into each other, heat is made, like rubbing your hands together. This is the heat that does the cooking.