What is sound?


What is sound?

A sound is caused by something vibrating, in other words, it is caused by something that moves from a side to other, in a regular or aleatory way. The source of the sound can be the motor of a car, an alarm or the bird singing, anything must be vibrating to produce a sound.

We could define sound like something that brain decodes using electrical impulses from ears, on contrary of eyes, we cannot close the ears, we can say that hear is one of the most important senses. We are continually subject to a great number of different types of sound, some of them are pleasant as speeches and music, and others are unpleasant and annoying, as the noise of machineries and highways.

The vibrations of a source of sound cause that neighboring molecules are alternately pressed and pushed one to each other. This succession of pressure fluctuations is what we call a sound wave, which is a longitudinal mechanical wave that spreads through an elastic medium. Most gives sounds we hear are transmitted by the air.

Sound is often represented by a sinewave, but physically it is a longitudinal wave (in the air) and its movement goes in direction of the movement of energy. When sound waves reach the ear of someone, these structure vibrations that cause electric signs which are send to the brain.