Question

Diagnostic ultrasound of frequency 3.82 MHz is used to examine tumors in soft tissue. (a) What is the wavelength in air of such a sound wave? (b) If the speed of sound in tissue is 1650 m/s, what is the wavelength of this wave in tissue? (Take the speed of sound in air to be 343 m/s.)

Answer 1

Step-by-step explanation:

It is given that,

Frequency of diagnostic ultrasound, f = 3.82 MHz = 3820 Hz

The speed of the sound in air, v = 343 m/s

(a) We need to find the wavelength in air of such a sound wave. Let it is given by λ₁

i.e.
`\lambda=(v)/(\\u)`

`\lambda_1=(343\ m/s)/(3820\ Hz)`

`\lambda_1=0.089\ m`

(b) If the speed of sound in tissue is 1650 m/s .

`\lambda_2=(v)/(\\u)`

`\lambda_2=(1650\ m/s)/(3820\ Hz)`

`\lambda_2=0.43\ m`

Hence, this is the required solution.