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Question
A sound wave travels at a speed of 339 m s−1. If its wavelength is 1.5 cm, what is the frequency of the wave? Will it be audible?
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Solution
Speed of sound wave, v = 339 m s−1
Wavelength of sound wave, `lambda` = 1.5 cm = 0.015 m
Speed of sound wave = Wavelength × Frequency
`"v"=lambdaxxupsilon`
∴ `upsilon`
= `"v"/lambda`
= `339/0.015`
= 22600 Hz
The frequency range of audible sound for humans lies between 20 Hz to 20,000 Hz. Since the frequency of the given sound is more than 20,000 Hz, it is not audible.
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