Transmission of the sound wave from one medium to the next is determined by:

The transmission of sound waves from one medium to another is fundamentally determined by the acoustic impedance of the media involved. Impedance is a critical factor that combines the density of the medium and the speed of sound within it, impacting how efficiently sound can pass from one medium to another.

When sound waves encounter a boundary between two different media, the difference in impedance influences how much of the sound wave is transmitted versus how much is reflected. If the impedances are closely matched, more sound energy will be transmitted into the second medium; conversely, if the impedance difference is large, a significant portion of the sound may be reflected rather than transmitted.

So, understanding impedance and its relationship with density and stiffness is essential in sonography, as it informs how sound interacts with different tissues, which in turn affects imaging quality and diagnostic capabilities.