In which unit is acoustic impedance represented?

Acoustic impedance is represented in the unit of Rayls. This measurement quantifies how much resistance a sound wave encounters as it travels through a medium. Specifically, acoustic impedance is defined as the product of the density of the medium and the speed of sound in that medium. Therefore, its units reflect the medium's properties, leading to the unit of Rayls, which is expressed in kg/(m²·s).

Using Rayls can be crucial in sonography, as it helps in understanding how sound interacts with different tissues, which assists in making diagnoses based on the reflection and transmission of ultrasound waves. In contrast, while decibels measure sound intensity levels, Hertz measures frequency, and Pascals measure pressure, none of these provide insight into the resistance the medium presents to the acoustic wave, which is the essence of acoustic impedance.