Page 76 - General_Knowledge_7

Tell me how?

What role is played by a magnetron in a microwave oven ?

A magnetron is a machine in the oven.
It sends out microwaves which make
the tiny water particles in food move
around. Heat is formed when these
particles rub against each other

which cooks the food.

Certain facts about microwaves
• Microwaves are drawn to food
which contain water.

• Material like glass or china
allow microwaves to pass right
through.

• They are reflected by aluminium
Browning the food
foil but go through plastic wrap.
Microwaves cook food by How do microwaves make water
heating the water on the particles or molecules hot ?
surface or inside the food. • When water particles or
Food doesn’t turn brown molecules are hit by microwaves
with microwaves alone, just they vibrate and move around.
as it doesn’t brown when it is When these particles rub
steamed. Certain microwave against other molecules they
ovens have another kind of produce friction and a great
heater which will brown deal of heat, as these particles
the food after it’s cooked by have uneven shapes.
the microwaves. Food looks
more delicious that way. • Water molecules have uneven
shapes.
When heat is applied to the
food directly, it will burn. • Your hands get warm if you
With microwaves the food rub them together. The heat is
isn’t browned even through produced by the same principle
it’s cooked. of friction.

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