As a general rule, sound travels fastest in solids, slower in liquids, and slowest in gases. Which ordering best describes this variation?

As a general rule, sound travels fastest in solids, slower in liquids, and slowest in gases. Which ordering best describes this variation?

• A. Solids, Liquids, Gases
• B. Gases, Liquids, Solids
• C. Liquids, Gases, Solids
• D. Solids, Gases, Liquids

Answer: (A)

Sound speed depends on how quickly vibrations can be transmitted through a medium, which comes from how stiff the medium is and how dense it is. In solids, the rigid lattice and strong interparticle forces let vibrations travel quickly, so sound moves fast. In liquids, the material is less stiff and particles can flow, which slows the transfer of energy compared with solids, though they’re still quite dense, so sound is faster than in gases. In gases, particles are far apart and interactions are weak, so vibrations spread much more slowly. Putting that together, the fastest sound is in solids, then in liquids, and slowest in gases.

Sound speed depends on how quickly vibrations can be transmitted through a medium, which comes from how stiff the medium is and how dense it is. In solids, the rigid lattice and strong interparticle forces let vibrations travel quickly, so sound moves fast. In liquids, the material is less stiff and particles can flow, which slows the transfer of energy compared with solids, though they’re still quite dense, so sound is faster than in gases. In gases, particles are far apart and interactions are weak, so vibrations spread much more slowly. Putting that together, the fastest sound is in solids, then in liquids, and slowest in gases.