Sound is not represented as a transverse wave; it is a longitudinal wave. In a longitudinal wave, the particles of the medium vibrate parallel to the direction of wave propagation. This means that the displacement of particles is in the same direction as the wave is traveling.
In the case of sound waves, they are generated by the vibration of a source, such as a speaker or a vibrating object. The vibrations of the source create regions of compression and rarefaction in the medium (usually air). These regions of compression and rarefaction propagate away from the source as a longitudinal wave.
To understand how sound is represented as a longitudinal wave, consider a simple example. Imagine a tuning fork vibrating in air. As the tuning fork moves back and forth, it compresses and rarefies the air particles around it. This compression and rarefaction form a series of alternating regions of high pressure (compression) and low pressure (rarefaction). These regions of compression and rarefaction move away from the tuning fork as the sound wave travels.
Although we often represent sound waves graphically as transverse waves, with peaks and troughs, it's important to note that this is just a visual representation and not an accurate depiction of the physical nature of sound waves. In reality, sound waves are longitudinal, with areas of compression and rarefaction propagating through the medium.