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Microwaves are a form of high frequency radio
waves similar to those used by a radio including AM,
FM and CB. They are, however, much shorter than
radio waves; approximately 12 cm long. Electricity is
converted into microwave energy by the magnetron
tube. From the magnetron tube, microwave energy is
transmitted and absorbed.
Reflection
Microwaves are reflected by metal just as a ball is
bounced off a wall. A combination of stationary
(interior walls) and rotating antenna, located
underneath the bottom shelf and above the ceiling
cover assure that the microwaves are well
distributed within the oven cavity to produce even
heating or cooking of foods.
transmission
Microwaves pass through some materials such as
paper, glass and plastic much like sunlight shining
through a window. Because these substances do not
absorb or reflect the microwave energy, they are
ideal materials for microwave oven cooking
containers.
absorption
During heating, microwaves will be absorbed by
food. They penetrate to a depth of about 1–5 cm.
Microwave energy excites the molecules in the food
(especially water, fat and sugar molecules), and
causes them to vibrate at a rate of 2,450,000,000
times per second. This vibration causes friction, and
heat is produced just as you will feel heat produced
if you vigorously rub your hands together. The
internal heating of larger foods is done by
conduction. The heat which is produced by friction
travels by conduction to the centre of the food.
Foods also continue to heat by conduction during
standing time.
Because microwaves dissipate, much like sunlight
as It reaches the Earth’s surface, they are not stored
in food.
Radio Interference
1. Operation of the microwave oven may cause
Interference to your radio, TV or similar
equipment.
2. When there is interference, it may be reduced or
eliminated by taking the following measures:
a) Clean the door and sealed surfaces of the
oven. (See Care of Your Microwave Oven
found on page 11.)
b) Place the radio, TV, etc. as far away as
possible, from the microwave.
c) Use a properly installed antenna, to obtain
stronger signal reception.
how does the Microwave work?
