Wave propagation in media: In which medium does sound travel at the fastest speed? Compare typical speeds in gases, liquids, and solids; assume standard conditions and homogeneous media.

Given factsSound requires a medium. Its speed v ≈ √(elastic modulus / density).

ReasoningSolids have much higher bulk/shear moduli than liquids or gases, so despite higher density, v is largest in solids (e.g., steel ~5000–6000 m/s > water ~1500 m/s > air ~343 m/s).

Final AnswerSteel (solid)