What term refers to the material through which a wave travels?

• A. Vacuum
• B. Conductor
• C. Medium
• D. Substance

Answer: (C)

The main idea is that a medium is the material through which a wave travels. For many waves, especially mechanical ones like sound, the energy is passed along by particles in the substance, whether it’s air, water, or a solid. The medium determines how fast the wave moves and how it behaves as it propagates. A vacuum isn’t a medium because there are no particles to carry the wave for mechanical waves. A conductor refers to a material’s ability to conduct electricity and isn’t the general term for what carries a wave. A substance is any matter, but it’s too broad; the word that specifically describes what a wave moves through is medium.