What type of wave is a sound wave?

Sound waves are classified as longitudinal waves because they involve the oscillation of particles in the medium through which the sound travels. In a longitudinal wave, the particles of the medium move back and forth in the same direction as the wave itself. This creates regions of compression, where particles are closer together, and rarefaction, where they are spread apart.

Sound waves propagate through various media such as air, water, and solids, relying on the interactions between molecules to transfer the sound energy. As the vibrating object (like a speaker diaphragm or vocal cords) creates sound, it pushes on the adjacent particles in the medium, and those particles then push against their neighbors, transmitting the sound wave through the medium.

In contrast, transverse waves, like waves on a string or electromagnetic waves, involve particle movement that is perpendicular to the direction of wave propagation. Surface waves combine aspects of both longitudinal and transverse waves but are more relevant in contexts such as ocean waves. Hence, the nature of sound waves as longitudinal is pivotal for understanding how sound is generated and how it travels through different environments.