Question
Write the applications of beats.

Answer

Beats are used to:
  1. Determine an unknown frequency by listening to the beat frequency $\Delta \text{v}.$ Then unknown frequency $\text{v}'=\text{v}+\Delta\text{v}$ where v is known and it is close to the unknown frequency. Exact values of v is found by loading and filling the turning fork of unknown frequency from which + or - sign is chosen;
  2. Tune musical instruments by sounding them together and reducing beats number to zero.
  3. Make a sound rich in musical effect by deliberate introduction of beats between different musical instruments.
  4. To produce very low frequency pulses which otherwise cannot be produced. Beat frequency is the low frequency sound.
  5. Receive radio programme by superheterodyne method.
  6. Detect harmful gases in mines.

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