A bat emits ultrasonic sound of frequency 100 kHz in air. If this sound meets a water surface, the wavelengths of the reflected and transmitted sound are (Speed of sound in air = 340 ms-1 and in water = 1500 ms-1)

Question

A bat emits ultrasonic sound of frequency 100 kHz in air. If this sound meets a water surface, the wavelengths of the reflected and transmitted sound are (Speed of sound in air = 340 ms-1 and in water = 1500 ms-1) (A) 3.4 mm, 30 mm (B) 6.8 mm, 15 mm (C) 3.4 mm, 15 mm (D) 6.8 mm, 30 mm

Tardigrade Admin · Accepted Answer

Here, upsilon = 100 kHz = 100 × 103 Hz = 105 Hz = 105 s-1 va = 340 ms-1, vw = 1500 ms-1 Frequency of both the reflected and transmitted sound remains unchanged. Wavelength of reflected sound, λa = (va/ upsilon) = (340 ms-1/105 s-1) = 34 × 10-4 m = 3.4 ×10-3 m = 3.4 mm Wavelength of transmitted sound, λw = (vw/ upsilon) = (1500 ms-1/105 s-1) = 15 × 10-3 m = 15 mm

Q. A bat emits ultrasonic sound of frequency $100 k Hz$ in air. If this sound meets a water surface, the wavelengths of the reflected and transmitted sound are (Speed of sound in air $= 340 m s^{- 1}$ and in water $= 1500 m s^{- 1}$ )

$3.4 mm$ , $30 mm$

$6.8 mm$ , $15 mm$

$3.4 mm$ , $15 mm$

$6.8 mm$ , $30 mm$

Q. A bat emits ultrasonic sound of frequency 100kHz in air. If this sound meets a water surface, the wavelengths of the reflected and transmitted sound are (Speed of sound in air =340ms−1 and in water =1500ms−1)

3.4mm, 30mm

6.8mm, 15mm

3.4mm, 15mm

6.8mm, 30mm

Q. A bat emits ultrasonic sound of frequency $100 k Hz$ in air. If this sound meets a water surface, the wavelengths of the reflected and transmitted sound are (Speed of sound in air $= 340 m s^{- 1}$ and in water $= 1500 m s^{- 1}$ )

$3.4 mm$ , $30 mm$

$6.8 mm$ , $15 mm$

$3.4 mm$ , $15 mm$

$6.8 mm$ , $30 mm$