Which type of wave is a sound wave classified as?

A sound wave is classified as a longitudinal wave because it propagates through a medium by the vibration of particles in the same direction as the wave travels. In a longitudinal wave, the particles of the medium oscillate back and forth along the direction of the wave, creating areas of compression and rarefaction.

When a sound wave travels through air, for example, the air molecules compress together in areas of higher pressure and then spread out in areas of lower pressure, following the movement of the wave. This direct transmission of energy through these compressions and rarefactions is characteristic of longitudinal waves.

In contrast, transverse waves, such as water waves or waves on a string, involve particle motion that is perpendicular to the direction of wave propagation. Electromagnetic waves, like light, do not require a medium to travel and consist of oscillating electric and magnetic fields. Surface waves typically involve both longitudinal and transverse motions, such as those seen in ocean waves.

Thus, the classification of sound waves as longitudinal waves aligns with their behavior and the mechanism by which they transmit energy through different materials.