An ultrasonic source emits sound of frequency 220kHz in air If this sound meets a water surface, what is - Science - Sound

Question

An ultrasonic source emits sound of frequency 220kHz in air If this
sound meets a water surface, what is the wavelength of the
reflected sound
(At the atmospheric temperature, speed in air = 352m/s and in water
= 1 496m/s)
Answer is 1 6 * 10^-3 metre
Explain me how?

Manas Pant · Accepted Answer

Dear Student,
Frequency of the ultrasonic sound, ν = 220 kHz = 2
2x105 Hz
Speed of sound in air, va = 352 m/s
The wavelength (λr) of the reflected sound is
given by the relation:
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width="45" id="Object31">

=3522 2×105=160×10-5=1 6×10-3m

Regards

An ultrasonic source emits sound of frequency 220kHz in air. If this sound meets a water surface, what is the wavelength of the reflected sound. (At the atmospheric temperature, speed in air = 352m/s and in water = 1.496m/s) Answer is 1.6 * 10^-3 metre Explain me how?

An ultrasonic source emits sound of frequency 220kHz in air. If this sound meets a water surface, what is the wavelength of the reflected sound.
(At the atmospheric temperature, speed in air = 352m/s and in water = 1.496m/s)
Answer is 1.6 * 10^-3 metre
Explain me how?