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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.
Microwaving Principles
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 1
1
⁄
2
-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.
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.
HOW MICROWAVES COOK FOOD
13 Amp fused socket
Microwave Water Molecule Absorption Vibration
