to explore the world around us people received a gift from the nature of the ability to hear.Due to this we have the opportunity to enjoy the trill of birds and musical works, receive signals, warning of the danger and communicate with each other.
Considering the nature of the sound, physics gave an answer that we have to deal with mechanical waves.For distribution, you must have an elastic medium.The answer to the question of what is the speed of sound in a vacuum for ideal conditions (complete absence of matter) suggests itself.In a vacuum, it can not propagate.Sound velocity, respectively, equals zero.But this does not mean that there are no space in the comic acoustic phenomena.Some are quite explicable nature and directly related to the development of the cosmos man.The roar of engines in vehicles, the sound vibrations in the space shuttle.And some events have yet to find an explanation, for example, such as the sounds that accompany the cosmic glow, or a low-frequency "traces" of the spacecraft.
In different conditions the speed of sound is defined by practical value.Its spread affected by the presence of obstacles.Given that we are dealing with mechanical waves, we can observe how the sound goes around these obstacles.This phenomenon is called diffraction waves regard.Low wave it more amenable than high.The chorus, turning the corner, first "loses" a high voice, and then it becomes not hear the singers with a low tone.
The effect of sound waves on human health thought long before the opening of infrasound.The generator inaudible sound frequencies can affect the mood of large concentrations of people.For example, the physics of America's Robert Wood is credited with a rather unusual experiment.He carried the theater infrasound generator, turn it on and witnessed how all the spectators embraced unusual nervousness and anxiety.
Even such a phenomenon as the appearance of "flying Dutchmen" - ships with a dead team, trying to explain the influence of infrasonic frequencies generated sea abyss during a storm.
Given the nature of sound waves, it can be concluded that the speed of sound in different environments having different magnitude.It has been observed that sound propagates in gases at different speeds.In this active component does not influence the density of the gas, it depends on the molecular weight.
Liquids sound travels even faster.That's just bad human ear distinguishes it in this environment.Sound waves propagating in the water almost completely reflected from the eardrum.But even Leonardo da Vinci has found an original way to listen to underwater sounds.To this end, he suggested the use of the paddle into the water lowered.If we compare the speed of sound in air (331 m / s), and water (1435 m / s), it is possible to track the distinct advantage denser medium for distribution.
Solids beat all records.The speed of sound in them can be up to 5000 m / s.An interesting experience can be done with common rail, enclosing the ear.If someone in the distance hit it with a hammer, we can clearly hear two hits.The first - a sound information obtained by the spread of the metal, and the second - a wave that arrived by air.
for a huge number of physical phenomena the speed of sound is a kind of benchmark, the starting point for comparison.Modern fighter aircraft is considered the greatest achievement of his supersonic abilities.By measuring the time of passage of a certain portion of the sound wave, the distance can be determined with high accuracy.
use of sound effects in various spheres of human activity is striking for its diversity.
