Sound is a fundamental element in life for almost all humans and animals. So many things can be accomplished with sound. Music, one of the most important art forms, can be played hundreds, even thousands of different ways by manipulating sound. Our main form of communication is talking and listening to others speak. Sound can be explained through waves in a wave tank or through waves on a spring. All forms of waves have certain characteristics, which make sound waves no different than water waves created in a wave tank or waves created on a spring. These waves are simply different forms of energy, but all have intrinsic properties that make them similar. Like any waves, two sound waves can exhibit interference and can make the sound louder or cancel the sound out.
The phenomenon of a guitar string is a very good example of waves on a spring and standing waves. A guitar string is a standing wave because the string is fixed at both ends and can vibrate. The speed of the waves of a string depends on the tension and mass. Since the fundamental wavelength of a standing wave on a guitar string is twice the distance between the bridge and the fret, all six strings use the same range of wavelengths. The different pitch of the string depends on the wave speed. But if the strings all had different tensions it would be very hard to play, therefore if the guitar strings are roughly the same tension then the strings must be different masses. This is why the lower strings have a higher mass; they are made thicker by wrapping them in wire. This makes the guitar easier to play.
Communication with other life, without sound, would be much more complicated. The physics of communication is through talking and through hearing. The human voice is created from the larynx located in the throat. A different pitch of sound depends on how the larynx is manipulated. We hear these manipulations by using our ears, whether we want to or not. Hearing is not like speaking, you cannot simply turn off your ears. The ear is very sensitive and if it is exposed to either a deafening loud noise or an extended exposure to high pitched or loud sounds will cause the eardrum to rupture, permanent loss of hearing may be the aftermath. The human ear can detect a whisper that is as low as fifteen decibels or a blaring as noise is around 200 decibels. A decibel is an amount of energy needed to produce a change in sound.
Sound travels vastest through very elastic materials, such as steel. It travels nearly fifteen times faster in steel than as in air. When any object that is composed of an elastic material is disturbed, it will vibrate at its own special set of frequencies, which together form its special sound called natural frequency. When that object is forced to vibrate at one of its own natural frequencies, resonance occurs and the sound becomes much louder.
Experts say that sound travels at about 330 meters per second in dry air. When an object such as an airplane exceeds this speed, approximately 1200 kilometers per hour, a sonic boom is heard. When this is accomplished, a large amount of energy is released in the form of this sonic boom. When an abundant amount of sound waves are pushed up against the front end of the plane the loud boom is created. The actual sonic boom happens once the plane exceeds the sound barrier and huge release of energy occurs to create the sound.
Sound exists in thousands of different forms. Communication and music are merely the beginning; there is hundreds of other phenomenon that make a unique sound. While being a major element in everyday life it also brings us enjoyment, laughter, and fascination. Hearing may be the most important human sense and without sound we would miss so much of life. Sound is the fundamental key in communication in our way of life and will continue to be for years to come.