Which statement is true about sound speeds in different media?

Which statement is true about sound speeds in different media?

• A. Sound travels fastest in air.
• B. Sound travels at the same speed in all solids.
• C. Sound travels slowest in steel.
• D. Sound travels fastest in steel.

Answer: (D)

Sound travels fastest in a medium that is very stiff (high elasticity) and not too dense, because the stiffness lets compression waves move quickly from particle to particle. In solids, vibrations propagate much faster than in liquids or gases, and among common materials in this context, steel is one of the faster transmitters of sound. That’s why the statement that sound travels fastest in steel is true. Air has a lot of space between particles and low stiffness, so sound moves slowly there. Not all solids share the same speed—density and stiffness vary among materials—so saying they’re all the same isn’t correct. Saying sound is slowest in steel also contradicts steel’s high stiffness, which enables rapid wave transfer.

Sound travels fastest in a medium that is very stiff (high elasticity) and not too dense, because the stiffness lets compression waves move quickly from particle to particle. In solids, vibrations propagate much faster than in liquids or gases, and among common materials in this context, steel is one of the faster transmitters of sound. That’s why the statement that sound travels fastest in steel is true.

Air has a lot of space between particles and low stiffness, so sound moves slowly there. Not all solids share the same speed—density and stiffness vary among materials—so saying they’re all the same isn’t correct. Saying sound is slowest in steel also contradicts steel’s high stiffness, which enables rapid wave transfer.