A bat flying above a take emits ultrasonic sound of 100 kHz. When this wave falls on the water surface, it is partly reflected and partly transmitted. What are the wavelengths of the reflected and transmitted waves? The speed of sound in air is 340 ms –1 and in water 1450 ms–1.
3.4 mm and 1.45 cm
Frequency of sound (V) = 100 kHz = 105 Hz
Speed of sound in air
Speed of sound in water
Since the reflected wave travels in air, its wavelength is
Since the transmitted wave travels in water, its wavelengths is
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