What is air-borne sound?

• A. Kinetic energy of an object moves surrounding air, creating pressure waves that travel to the ear.
• B. Direct electrical signals traveling through the air.
• C. A vibration within the inner ear fluids.
• D. Sound produced by bone conduction.

Answer: (A)

Air-borne sound is a mechanical pressure wave traveling through air, created when something vibrates and pushes on the surrounding air, producing alternating compressions and rarefactions that reach the eardrum. The described scenario—an object vibrating and moving the surrounding air to generate pressure waves that travel to the ear—is exactly how sound travels through air. The other ideas describe different pathways or steps: direct electrical signals through air aren’t sound waves, vibrations inside the inner ear fluids occur after the wave has arrived and is being transduced, and bone conduction sends sound through the bones rather than through air.