Which among the following is true for propagation of sound waves ?

Sound is a mechanical wave that requires a material medium (solid, liquid, or gas) to propagate [1]. It travels through the oscillation of particles in the medium, creating regions of compression and rarefaction [1]. Because mechanical waves rely on particle interactions to transfer energy, sound cannot travel in a vacuum where no particles exist [1]. In air, sound waves are specifically longitudinal waves, meaning the particles of the medium vibrate back and forth in the same direction as the wave's propagation [1]. This distinguishes them from transverse waves, like light or seismic S-waves, where vibrations occur perpendicular to the direction of travel [1]. Therefore, sound is characterized as a longitudinal mechanical wave that is unable to propagate through a vacuum [1].

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 5: Earths Magnetic Field (Geomagnetic Field) > Why Do Sound Waves Travel Faster In A Denser Medium Whereas Light Travels Slower? > p. 64