Q5 of 118 Page 352

Find the minimum and maximum wavelengths of sound in water that is in the audible range (20—20000 Hz) for an average human ear. Speed of sound in water = 1450 m s-1.

Given:
Speed of sound in water v = 1450 ms−1



Audible range for average human ear = (20-20000 Hz)



Relation between frequency and wavelength with constant velocity:



(a) For minimum wavelength, the frequency should be maximum.


Frequency


As



⇒


⇒


(b) For maximum wave length, the frequency should be minimum.






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