Which statement describes the requirement for transmission in the boundary problem?

• A. Reflection information
• B. The use of the law of conservation of energy
• C. Ohm's law
• D. The use of Snell's law

Answer: (B)

When a wave meets a boundary between two media, energy must be conserved. Part of the wave’s energy is reflected back into the first medium, and part is transmitted into the second. The fundamental requirement here is that the total energy remains constant (ignoring losses): incident energy equals reflected energy plus transmitted energy. That energy-balance principle is what governs transmission across boundaries.

Snell’s law describes how the direction of the transmitted wave changes, but it doesn’t state how much energy is transmitted. Ohm’s law relates voltage, current, and resistance in electrical circuits, not boundary transmission of waves. Referring to “reflection information” isn’t the core requirement for transmission either; the essential idea is ensuring energy conservation as energy splits between reflection and transmission.