Question
A bat emits ultrasonic sound of frequency 100 KHz in air. If this sound meets a water surface, what is the wavelength of (a) the reflected sound, (b) the transmitted sound? [Speed of sound in air = 340 m/s Speed of sound in water = 1486 m/s]
Solution
(a) Frequency of wave,
Velocity of reflected wave 
∴ Wavelength, 
(b) Velocity of wave in water = 1486 m/s
Since the frequency of wave does not change on refraction, therefore wavelength of transmitted wave is,
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