With normal incidence, if the two media have the same impedance, _____ incident intensity is transmitted.

With normal incidence, if the two media have the same impedance, _____ incident intensity is transmitted.

• A. Some of the
• B. Most of the
• C. All of the
• D. None of the

Answer: (C)

When a wave meets a boundary at normal incidence and the two media share the same impedance, there is no reflected wave. The boundary presents no impedance mismatch, so all of the incident energy crosses into the second medium. Therefore the transmitted intensity equals the incident intensity, assuming the interface itself has no losses and there’s no immediate absorption at the boundary.

When a wave meets a boundary at normal incidence and the two media share the same impedance, there is no reflected wave. The boundary presents no impedance mismatch, so all of the incident energy crosses into the second medium. Therefore the transmitted intensity equals the incident intensity, assuming the interface itself has no losses and there’s no immediate absorption at the boundary.