The Basic Properties of Sound Essay

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First of all, a sound source radiates power and this results in a sound pressure, where the sound power is the ‘cause’ and sound pressure is the ‘effect’. But still, we always have to keep in mind that sound cannot travel through vacuum, simply, because sound propagates as a wave, which creates ‘compressions’ and ‘rarefactions’, as it interacts with the particles of the medium. If there is no medium, then there are no particles and of course, there is no interaction wave-particles interaction and as a result, no sound is produced. This specific fact, was proven by Robert Boyle (17th century), a researcher who showed through multiple experiments, that a bell, ringing in vacuum medium cannot be heard. We have to mention here, that sound …show more content…

The unit of frequency in SI (System International) is the hertz (Hz), where one hertz is equivalent to one cycle per second. Human beings can hear sound from vibrating objects in the range between 20-20.000 Hz (this range may vary depending on age, health, e.t.c.). Pitch, on the other hand is the human sensation of frequency, the ability to tell the difference between different frequencies of sound, which are organized into classes of pitches. A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to a low frequency sound wave. In music, pitch is a technical term, used to describe how high or low a note is.
Intensity vs Loudness
Sound intensity is defined as the sound power per unit area. We usually measure the intensity in a vertical direction (90o) in relation to a given unit area, through which the sound energy is flowing. Intensity is very useful in locating sound sources, since it provides a measure of direction and magnitude (SI unit: W/m2). The most common and easiest alternative way to measure sound intensity is by using the logarithmic decibel (dB) scale. The threshold of hearing is assigned a sound level of 0 dB (1*10-12 W/m2). A sound 10 times more ‘intense’ corresponds to a sound level of 10dB, a sound 100 times more intense corresponds to a sound level of 20dB and finally, a sound 1000 times more intense corresponds to a sound level of