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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
What are radio waves? Give its two uses.
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Answer

  1. Radio waves are produced by accelerated motion of charges in a conducting wire. The frequency of waves produced by the circuit depends upon the magnitudes of the inductance and the capacitance.
  2. Thus, by choosing suitable values of the inductance and the capacitance, radio waves of desired frequency can be produced.

Uses:

  1. Radio waves are used for wireless communication purpose.
  2. They are used for radio broadcasting and transmission of TV signals.
  3. Cellular phones use radio waves to transmit voice communication in the ultra high frequency (UHF) band.

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