The frequency of sound affects attenuation. What is one reason for this?

The reason low frequency sound attenuates less than high frequency sound is linked to the physical principles of how sound interacts with tissue. Higher frequency sound waves have shorter wavelengths, which leads to increased energy absorption by tissues. This results in greater attenuation, or reduction of sound intensity, as the sound waves travel through materials such as soft tissues, bone, and organs.

Lower frequency sound waves, conversely, have longer wavelengths and are able to penetrate deeper without as much loss of intensity. Consequently, they experience less attenuation. In clinical ultrasound, this principle is crucial because it informs the choice of frequency depending on the depth of the target structures and the desired image resolution.

While all sound frequencies undergo some degree of attenuation and sound amplitude does affect other characteristics like intensity, the frequency itself directly correlates with the extent of attenuation, making it an essential concept in understanding ultrasound imaging.