Which statement about the speed of sound in different media is true?

Which statement about the speed of sound in different media is true?

• A. It is the same in all media
• B. It depends only on density
• C. It depends only on compressibility
• D. It depends on the medium

Answer: (D)

Sound speed comes from how a material responds to a small pressure disturbance: how stiff it is (how easily it compresses) and how much mass has to be moved (its density). A medium that resists compression and has lower density lets the disturbance travel faster, while a softer, denser medium slows it down. That’s why air, water, and steel all have different speeds for the same phenomenon. Because the speed is determined by the specific properties of the material, it isn’t the same in every medium and isn’t set by density alone or by compressibility alone. It depends on the medium as a whole.

Sound speed comes from how a material responds to a small pressure disturbance: how stiff it is (how easily it compresses) and how much mass has to be moved (its density). A medium that resists compression and has lower density lets the disturbance travel faster, while a softer, denser medium slows it down. That’s why air, water, and steel all have different speeds for the same phenomenon. Because the speed is determined by the specific properties of the material, it isn’t the same in every medium and isn’t set by density alone or by compressibility alone. It depends on the medium as a whole.