Guide
1
physical phenomenon of sound is a pervasive disturbance of elastic waves.Medium for the spread of such a wave may be any material having a property of elasticity, i.e. liquid, gas or solid.As you know, for the propagation of any wave oscillation requires a parameter, which is transmitted from the wave.In the case of sound, such oscillations are oscillations of the coordinates of the particles of the medium.
2
sound wave has characteristics typical of any wave, ie, the amplitude and frequency of vibration frequency spectrum, the phase velocity of propagation.Each of the characteristics affect the outward manifestation of sound.The oscillation amplitude is expressed in the volume perceived by receivers such as the human ear or a microphone.The oscillation frequency indicates a pitch.As is known, a person is able to per
ceive sounds in the frequency range from 20 Hz to 20 kHz.Therefore, the entire frequency range of the sound can be divided into two components: a low-frequency (ie below 20 Hz) is called infrasound and high-frequency - ultrasound.
3
From the standpoint of physics of sound wave vibrations of the medium particles lead to oscillations of the density and pressure of its layers.The above example, the volume, the more pressure the air layers are sealed.It is also known that the human perception of loudness depends on the pitch.
4
frequency spectrum of the sound wave is characterized by the tone of the audible sound.The more spectral components have a wave, the more harmonics can be distinguished.
5
worth noting that, in fact, the sound wave consists of a set of highly compressed and rarefied layers of material.Each layer moves in space, taking the place of the nearest layer wading and thereby to the receiver.
6
Since sound is a wave process, he is characterized by wave phenomena such as diffraction and interference.Diffraction of sound allows you to hear the source, while for any obstacle.If the sound wave was not able to diffract, it was impossible to hear the speech of a person in the next room or just outside the fence.Interference sound becomes noticeable only in special physical experiments.
7
sound wave has a definite velocity of propagation equal to 340-344 m / s.This value depends on the propagation environment, its density.For example, the velocity of sound in liquids is greater than in gases, and solids larger than in liquids.