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2 HOW DO MICROWAVES WORK?
Microwaves function without contact to a heat source. A microwave device has an effect
only on liquids. It doesn’t matter if the liquid is visible, like water, or if the liquid is in the
food. The microwaves make contact with the water molecules and let them move. By the
movement heat is generated. The longer the microwaves make contact with the molecules
the faster they move and the more heat is produced. This heat penetrates the entire food
and leads to defrosting, heating or cooking of the food.
The metallic interior walls of the cooking chamber and the cooking chamber door with
metal grids reflect impinging microwaves into the cooking chamber and to the food.
When opening the door of the cooking chamber the microwave turns off immediately to
avoid the transmission of microwave radiation to the outside.
The microwave does not heat up solid objects, for example a ceramic bowl: in the cera-
mic is no liquid to bring into movement. No movement energy is produced and no heat.
Still you should be careful: even if the container is not heated by the microwaves, it will
be heated by the food inside.
During microwave operation food is not always heated evenly. This is caused because
there are places in the cooking chamber where particularly much energy is available and
in other places there is no energy. The rotary plate ensures an even heat distribution.
During operation it turns the food in the cooking chamber, where the microwaves act
evenly onto the food.