What is the propagation speed of bone?

What is the propagation speed of bone?

• A. 1,460 m/s
• B. 1,555 m/s
• C. 1,600 m/s
• D. 4,080 m/s

Answer: (D)

The speed of sound in a material is mainly determined by how stiff it is relative to its density: stiffer materials transmit vibrations faster. Bone, especially cortical bone, is extremely stiff compared to soft tissues, so it carries ultrasound waves much quicker. In practice, soft tissues like fat and muscle run around 1,450–1,600 m/s, while cortical bone typically falls near 4,000 m/s. That makes a propagation speed around 4,080 m/s the correct match for bone, since it reflects bone’s high stiffness and density relative to soft tissue.

The speed of sound in a material is mainly determined by how stiff it is relative to its density: stiffer materials transmit vibrations faster. Bone, especially cortical bone, is extremely stiff compared to soft tissues, so it carries ultrasound waves much quicker. In practice, soft tissues like fat and muscle run around 1,450–1,600 m/s, while cortical bone typically falls near 4,000 m/s. That makes a propagation speed around 4,080 m/s the correct match for bone, since it reflects bone’s high stiffness and density relative to soft tissue.