In which biological tissue will sound travel the fastest?

In which biological tissue will sound travel the fastest?

• A. Tendon
• B. Blood
• C. Lung
• D. Fat

Answer: (A)

Sound speed in tissue follows how stiff the material is and how dense it is. In general, stiffer tissues transmit pressure waves faster because the wave can push the surrounding matrix more efficiently, while higher density can slow things down a bit. Tendon is extremely stiff due to its dense collagen structure, so longitudinal waves propagate through it quickly. Blood and fat are softer and more compressible, so waves travel more slowly in them. The lung contains a lot of air, which drastically lowers the effective speed of sound, making it slower than the other tissues here. So, tendon transmits sound fastest among these tissues because its high stiffness dominates the propagation, outpacing the softer blood, fat, and the air-filled lung.

Sound speed in tissue follows how stiff the material is and how dense it is. In general, stiffer tissues transmit pressure waves faster because the wave can push the surrounding matrix more efficiently, while higher density can slow things down a bit.

Tendon is extremely stiff due to its dense collagen structure, so longitudinal waves propagate through it quickly. Blood and fat are softer and more compressible, so waves travel more slowly in them. The lung contains a lot of air, which drastically lowers the effective speed of sound, making it slower than the other tissues here.

So, tendon transmits sound fastest among these tissues because its high stiffness dominates the propagation, outpacing the softer blood, fat, and the air-filled lung.