The velocity of sound waves is primarily dependent on which of the following factors?

The velocity of sound waves is primarily dependent on the material through which they are being transmitted. This is because different materials possess distinct physical properties, such as density and elasticity, which influence how quickly sound can travel through them. For instance, sound waves travel faster in solids than in liquids, and faster in liquids than in gases due to differences in molecular structure and bonding.

While other factors like temperature can also affect sound speed—typically causing sound to travel faster in warmer mediums—it's the inherent properties of the material itself that have the most significant impact. The type of transducer used or the frequency of the sound waves play roles in the generation and detection of sound waves, but they do not fundamentally alter the velocity of sound in a given material. Understanding this principle is crucial in applications of Ultrasonic Testing (UT), where the choice of material plays a key role in evaluating the results of sound velocity measurements.