What is the size of the smallest feature observable in human tissue when examined with 10-MHz ultrasound?

Question

Ultrasound probes can resolve structural details with sizes approximately equal to the wavelength of the ultrasound waves themselves. What is the size of the smallest feature observable in human tissue when examined with 10-MHz

 ultrasound? The speed of sound in human tissue is 1,540 m/s.

Answer 1

We know that:

f = frequency of ultrasound = 10-MHz = 10x10⁶ Hz

v = speed of ultrasound = 1540 m/s

 = wavelength of tissue = ?

We can find wavelength by using the equation:

 = v / f

 = 1540 / (10x10⁶)

= 154 x 10^-4 m

= 154 m