If IRC and ITC are added, what must their total equal?

In the context of ultrasound physics, the terms IRC (Incident Reflected Coefficient) and ITC (Incident Transmitted Coefficient) refer to the portion of the ultrasound wave energy that is reflected back into the medium and the portion that is transmitted into the next medium, respectively.

When an ultrasound wave strikes an interface between two different media (for example, soft tissue and bone), a portion of the wave is reflected and a portion is transmitted. The fundamental principle is that the total energy must equal 100% when you consider all the energy being either reflected or transmitted. This is due to the law of conservation of energy, which states that energy cannot be created or destroyed; it can only change forms. Therefore, if you take the portion of energy reflected (IRC) and the portion transmitted (ITC) and add them together, their total must always equal the total incident energy that was introduced, which is 100%.

In summary, when IRC and ITC are added together, their total reflects the complete interaction of the ultrasound wave with the interface, confirming that the combined coefficients must equal 100%. This understanding is crucial in the field of sonography, as it helps in accurately assessing and interpreting ultrasound wave behavior at interfaces.