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Waves

Electromagnetic Waves - What are Microwaves?

Microwaves are part of the electromagnetic spectrum.
Microwaves have wavelengths that are shorter than radio waves.


How are Microwaves Used for Communication?

Microwaves have some wavelengths that pass easily through
the atmosphere and they are used to transmit information
to satellites. Satellite TV and mobile phone (or smartphone)
networks use microwaves. Some people have concerns
that microwaves from mobile phones may be harmful.
However, the intensity of the microwaves emitted from mobile
phones
is low and the evidence for their safety is not conclusive.


How are Microwaves Used for Cooking?

Some microwaves have wavelengths that are absorbed by
water molecules. Microwave cookers use waves which give energy
to the water molecules in food, causing the food to get hot.
The cooker has a metal door screen and outer case which
absorb or reflect microwaves to protect people who use the cooker.


How can Microwaves cause Harm?

Living cells can absorb microwaves. The cells
may be damaged or killed by the
heating effect of the waves. Skin cells can be burned.

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