Sound waves are created by the vibrations that occur in molecules. In this article, you’ll learn what makes up a sound, why it’s difficult to change someone’s voice without surgery, and why some sounds seem to have different meanings.
What is Sound?
Sound is a type of energy that travels through the air, or any other medium, as a vibration of pressure waves. The human ear can detect sound waves with frequencies between 20 Hz and 20 kHz. These frequencies are what make up the different sounds we hear.
The speed of sound in a particular medium is determined by three factors: the medium’s density, its temperature, and the pressure inside the medium. Sound travels faster in water than in air, for example, because water has more mass and less compressibility than air.
Because sound waves travel through space and interact with objects they encounter along the way, they can be distorted (or “attenuated”) by these objects.
This distortion creates unique sounds that we recognize as belonging to certain categories, such as speech sounds (like “buh”) or musical notes (like C-sharp).
How do we Hear the Sound?
When we hear a sound, our auditory system starts working to create a representation of the sound. Our auditory system consists of three parts: the outer ear, the middle ear, and the inner ear.
The outer ear is responsible for hearing low-frequency sounds like those that you hear when you are on an airplane. These sounds travel through the air and hit your eardrum. The eardrum vibrates and causes pressure waves to be created in your inner ear.
These pressure waves travel up your cochlea, which is the organ in your inner ear that converts these pressure waves into electrical impulses. The electrical impulses travel along hair cells and pass through the minuscule membrane that separates them from nerve cells in your brain.
The middle ear is responsible for hearing high-frequency sounds like those you hear when somebody talks to you. These sounds travel through the air and hit your eardrum. The eardrum doesn’t vibrate as much as it does with low-frequency sounds, so the pressure waves don’t create as many electrical impulses.
The vibrations from the eardrum cause fluid to escape from your tympanic cavity (the space behind your drumhead) and move around inside your head. This movement creates a sense of motion that our brains interpret as sound.
The inner ear is responsible for hearing all other sounds including those that are too high or too low frequency for our middle or outer ears to detect.
How do Sounds Change as they Move through Space?
Sounds travel through the air and other mediums at different speeds depending on their wavelength. Longer wavelengths move slower than shorter wavelengths, and high-pitched sounds travel faster than low-pitched sounds.
This is due to how our hearing works. Our ears are able to detect low-frequency sound waves because they move through the air more slowly than higher-frequency sound waves.
This is why it is difficult to hear someone speak in a room full of people if they are speaking at a high-pitched pitch.
How are Sounds Produced and Transmitted?
Sound is a type of energy that travels through the air as waves. These waves are created by a vibration of air molecules. Sound waves can be heard when they pass through the ear canal, and they can also be seen or felt with the skin.
How do Sounds Have Distinct Identities?
There are many factors that contribute to the unique sound of each object. One important factor is the shape and size of the object’s vibrating surfaces.
This includes things like the surface area of a drumhead, the length, and thickness of a guitar string, or the number and size of cells in an acoustic guitar’s body.
The size, shape, and material properties of an object also affect how quickly these surfaces vibrate. This determines how long sound waves will take to travel from one end of the object to another. Longer sound waves produce louder sounds, while shorter waves produce softer sounds.
Another critical factor is how well an object amplifies sound waves. This depends on a few things, including how thick the walls are between adjacent sound chambers, how well those chambers are sealed off from each other, and how porous (or absorbent) the walls are around those chambers. The more porous the walls are, the easier it is for sound energy to seep into and amplify nearby sounds.
When you listen to music, watch a movie or read a book, you are experiencing the sound of that specific thing. The artist has specifically designed the sounds in these scenarios, and they carry with them certain emotional characteristics that make them special.
In this article, we explored how sound works and why it has different identities depending on the environment in which it is heard.
We also explored how listeners can manipulate the way sound affects them through their own behavior. So next time you’re listening to your favorite song or watching a movie scene, take some time to appreciate all of the science that goes into making those sounds so pleasurable for us humans!