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Answer :

For sound waves,

Speed = Wavelength × frequency

\( v = \lambda × v \)

Speed of sound wave in air = 344 m/s

(a) For v = 20 Hz

\( \lambda_1 = \frac{v}{v_1} = \frac{344}{20} = 17.2 m \)

(b) For \( v_2 = 20,000 Hz \)

\( \lambda_2 = \frac{v}{v_2} = \frac{344}{20,000} = 0.0172 m \)

Therefore, for human beings the hearing wavelength is in the range of 0.0172 m to 17.2 m.

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