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Electromagnetic Waves and Communication System — Physics STD 11 Science — Question

Maharashtra BoardEnglish MediumSTD 11 SciencePhysicsElectromagnetic Waves and Communication System4 Marks
Question
How are microwaves produced? State their properties and uses.
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Answer

Production:
  1. Microwaves are produced by oscillator electric circuits containing a capacitor and an inductor.
  2. They can be produced by special vacuum tubes.
Properties:
  1. They heat certain substances on which they are incident.
  2. They can be detected by crystal detectors.
Uses:
  1. Used for the transmission of TV signals.
  2. Used for long distance telephone communication.
  3. Microwave ovens are used for cooking.
  4. Used in radar systems for the location of distant objects like ships, aeroplanes etc,
  5. They are used in the study of atomic and molecular structure.

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