Question

Ultrasonic waves of frequency $3\times {10}^{5}Hz$ are passed through a medium where speed of sound is 10 times that in air (Speed of sound in air is 300 m/s). The wavelength of this wave in that medium will be of the order of _________.

• A. 1 cm
• B. 10 cm
• C. 100 cm
• D. 0.1 cm

Answer 1

The correct option is A 1 cm

Given, frequency(f) = $3\times {10}^{5}Hz$

Speed of sound in medium = $10\times V_{a}ir$

=$10\times 300$ = 3000m/s
V =$f\lambda$

= $\frac{V}{f}$

= $\frac{3000}{3\ast {10}^5}$

= ${10}^{-}2$

$=100m=1cm$