Panasonic NN-CF768M Microwaving Principles, How Microwaves cook food, Reflection, Transmission

Microwaving Principles

Microwave energy has been used in this country to cook and reheat food since early experiments with RADAR in World War II. Microwaves are present in the atmosphere all the time, both naturally and from manmade sources.

Manmade sources include radar, radio, television, telecommunication links and car phones.

How Microwaves cook food

Oven cavity

Magnetron

Ceramic Plate

Microwave Stirrer

Stirrer Motor

Waveguide

In a microwave oven, electricity is converted into microwaves by the MAGNETRON.

REFLECTION

The microwaves bounce off the metal walls and the metal door screen.

TRANSMISSION

Then they pass through the cooking containers to be absorbed by the water molecules in the food, all foods contain water to a more or lesser extent.

The microwaves cause the water molecules to vibrate which causes FRICTION, i.e. HEAT. This heat then cooks the food. Microwaves are also attracted to fat and sugar particles, and foods high in these will cook more quickly.

Microwaves can only penetrate to a depth of 1½ -2 inches (4-5 cm) and as heat spreads through the food by conduction, just as in a traditional oven, the food cooks from the outside inwards.

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