Write source of microwaves and their uses.

Explanation

Microwaves are produced by special type of vacuum tubes like Klystron, magnetron or Gun diodes.
They are radio waves of very short wavelength and range varies from 0.3 GHz to 300 GHz.
Uses :
(i) They are used in radar systems used in aeroplane and navigation.
(ii) They are used for control of fighter plane, navy and satellite communication.
(iii) Radar provides basis for speed of ball, (tennis and cricket), speed Gun used to measure speed of vehicles.
(iv) It is used in microwave ovens.
In such oven frequency of microwave resonate with frequency of water molecules. Hence, energy of wave is transmitted in form of kinetic energy of water molecules. Hence it can be used to heat food containing water molecules.
Domestic microwave oven use 0.915 GHz or 2.45 GHz to cook food or warm up food.