The percentage of the sound beam's intensity that passes through when the beam reaches a boundary between two media is called the ITC.

• A. Transmittance
• B. Reflectance
• C. IRC
• D. ITC

Answer: (D)

The amount of energy that continues into the second medium after crossing a boundary is described by the intensity transmission coefficient (ITC). ITC is the ratio of transmitted intensity to incident intensity, usually expressed as a percentage, and it tells you how much of the beam’s energy actually passes through the boundary. The energy not transmitted is reflected, described by the intensity reflection coefficient (IRC), and in non-absorbing media the transmitted plus reflected energy adds up to the incident energy. Transmittance is a closely related idea, but ITC is the specific term used for the fraction of energy that passes through in this context, making it the best fit.