Ultrasound - What is the size of the smallest feature observable

[brickman7713]

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

 

Thanks!

[studiot]

So did you actually attempt this?

A hint : what sort of phenomenon is ultrasound and what do you know about waves?

[StringJunky]

If the speed of sound is 1540 m/s, which means that, in one second, a one hertz (1 cycle) wave will be 1540 metres long, a 2 hertz wave will 1540/2 metres long. The formula you want to be using is the distance sound travels in one second divided by the frequency. How long will a wave be that is 11 million hertz? 

Edited April 21, 2019 by StringJunky

[brickman7713]

23 hours ago, StringJunky said:

If the speed of sound is 1540 m/s, which means that, in one second, a one hertz (1 cycle) wave will be 1540 metres long, a 2 hertz wave will 1540/2 metres long. The formula you want to be using is the distance sound travels in one second divided by the frequency. How long will a wave be that is 11 million hertz? 

Okay so it's just 1540/11 million. Got it, thanks!

[Conscious Energy]

0.1 mm urinstones, 1mm in diameter blod vessels. 0,1 mm thick urinblader and gall blader walls, tricuspidal valves.

It depends a lot from the resolution of the Ultrasound machine. 

Edited April 4, 2021 by Conscious Energy