Hearing is one of the most important senses of the human body. We use it everyday in our daily lives, and we hear as much or more than we see, feel, taste, and smell. What do we exactly hear? The answer to that question is sound. What exactly is sound though, and how is it created? Sound is a series of vibrations that travel through air or another platform and heard when it reaches the ear of a person or animal. In more simpler terms, sound is a form of energy that spreads out through space. What is the source of all sound? In one word, vibration.
A major facet to understanding this concept is pitch. What exactly is pitch? Pitch is what refers to the frequency of the sound. A high pitched sound has a high vibration frequency, while a low pitched sound has a low vibration frequency. The pitch range of frequency is from about twenty hertz to twenty-thousand hertz. The more we age, our hearing range goes down or shrinks, more specifically at the end of high frequency.
Sound waves with frequencies below twenty hertz are called infrasonic. As for sound waves with frequencies above twenty-thousand hertz are called ultrasonic. Unfortunately for humans, the hearing of infrasonic and ultrasonic are unavailable. However dogs and bats can hear way better than humans. Dogs can listen to frequencies of over forty-thousand hertz and bats can hear over frequencies of over one hundred thousand hertz.
There are two more very important topics to be discussed when it comes to comprehending sound. These two include compressions and rarefactions. Compression is the pulse of compressed air. Rarefaction is the pulse of low-pressure air. An example of both of these happening in the real world is when someone both opens and closes a door. When someone opens a door, a compressions goes throughout the room. As for when someone closes a door, a rarefaction travels throughout the room. This is why when someone closes a door, a curtain moves. For all wave motion, it is not the surface and or the medium that travels across the room, but the pulse that does. Proof for this being true is when the curtain moves when someone closes a door.
In an overall summary, sound is a very important concept that needs to be understood. The main points include that sound is created by vibrations. It travels through air or another platform that can be heard by someone. Basically, you can’t hear sound in an empty space such as outer space. Important concepts to be noted and understood regarding sound are what pitch is, compressions, and rarefactions.