Sound waves are literally what they sound like. Waves of sound. Now what’s incredible about those sound waves is that we, as human beings, are able to synthesize them and actually make coherent sense out of them. Take our voices, for example. Our voices are just rapid successions of sound waves at several different frequencies, and yet we can still use them to communicate with each other and create things that no other creature (that we know of) can create. So today, I’ll be taking you all through the science of sound waves and why we can make stuff out of them.
To put it bluntly, sound is all about vibration. The source of some sound, whether it be from your headphones or your own voice box, vibrates rapidly, which causes it to bump into the air nearby, causing them to bump into the neighboring air molecules, which causes them to bump into more neighboring air molecules, and you get the idea. That creates a wave, or, sound wave, which travels through our eardrums, which also vibrates. Now what that soundwave actually sounds like, however, depends on several different variables, like what medium it’s using to get to your ears or the amplitude (strength) of the vibration itself.
For us humans to actually hear a sound wave, those waves must be at certain speeds or frequencies. We obviously wouldn’t be able to hear the sound waves created by something like our hands when we wave them since they are simply too slow or too low of a frequency to be heard by the human ear. The smallest frequency we can hear is 20 Hz or 20 vibrations per second, which would produce a very low droning sound. The fastest vibration our ears can pick up is 20,000 Hz, which produces a sharp piercing sound that isn’t very pleasant. However, that number can change depending on your age. If you are very young, say newborn to 10 years old, you’d probably be able to hear all the way up to 20,000 Hz. The older you are, however, the less of a higher frequency you can hear, and it all has to do with how used your eardrums are. Older people have been alive longer, thus their ears have been used much more, making them less sensitive to sounds than say a newborn would.
And now for the portion behind why we can hear sound and comprehend it. As stated previously, sound is just vibrations, and hearing something is the body’s way of picking up those vibrations through the very special organ called our ears. These vibrations enter the outer ear, causing our eardrums to vibrate. Then, there are three very small and very delicate bones that vibrate along with the eardrum called the hammer, the anvil, and the stirrup. These three bones work together as an amplifier and send the stronger vibrations they produce into the inner ear for the auditory nerve to pick up and ship off to the brain where we quickly synthesize sounds like music or speech. So, if you ever sit there and question why you understand the things you hear and how you actually hear them, here’s your answer!