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Waves and Sound — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsWaves and Sound1 Mark
Question
Assertion : To hear distinct beats, difference in frequencies of two sources should be less than 10.
Reason : More the number of beats per sec more difficult to hear them.
✓

Answer

(b) According to the property of persistence of hearing, the impression of a sound heard persists on our mind for $\frac{1}{10} \mathrm{sec}$.Therefore, number of beats per sec should be less than 10. Hence difference in frequencies of two sources must be less than 10.

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