MCQ
It is possible to hear beats from the two vibrating sources of frequency
  • A
    $100 Hz$ and $150 Hz$
  • $20 Hz$ and $25 Hz$
  • C
    $400 Hz$ and $500 Hz$
  • D
    $1000 Hz$ and $1500 Hz$

Answer

Correct option: B.
$20 Hz$ and $25 Hz$
b
(b) For hearing beats, difference of frequencies should be approximately $10 Hz.$

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