To study the world around us, a person received the ability to hear as a gift from nature. Thanks to this, we have the opportunity to enjoy the trill of birds and musical works, to receive warning signals about danger and communicate with each other.
Considering the nature of sound, physicists answered that we are dealing with mechanical waves. Their propagation requires the presence of 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 cannot propagate. The speed of sound, respectively, is equal to zero. But this does not mean that there are no acoustic phenomena in the comic space . Some are quite understandable in nature and are directly related to the exploration of space by man. The roar of motors in ships, the sound vibrations inside space shuttles. And some phenomena have yet to find an explanation, for example, such as the sounds accompanying the cosmic glow, or low-frequency “traces” of spacecraft.
Under various conditions, the speed of sound has experimentally determined values. Its distribution is affected by the presence of obstacles. Given that we are dealing with mechanical waves, we can trace how sound goes around these obstacles. This phenomenon with respect to waves is called diffraction. Low waves are better suited to it than high. The chorus, which turned around the corner, at first “loses” high voices, and then singers with a low timbre become inaudible.
The influence of sound waves on human health was thought long before the discovery of infrasound. With the help of a generator of inaudible sound frequencies, you can influence the mood of a large crowd of people. So, physicist from America Robert Wood is credited with a rather unusual experiment. He brought an infrasound generator to the theater, turned it on, and witnessed how all the audience was seized by unusual nervousness and anxiety.
They even try to give an explanation to the influence of the infrasound frequencies generated by the depths of the sea during a storm, even such a phenomenon as the appearance of "flying Dutch" - ships with a lost crew.
Given the nature of the propagation of sound waves, we can conclude that the speed of sound in a different medium has a different value. It has been observed that sound travels in gases at different speeds. Moreover, the density of gases does not affect this indicator , it depends on the mass of molecules.
In liquids, sound travels even faster. But the human ear does not distinguish it in such an environment. The sound wave propagating in water is almost completely reflected from the eardrum. But even Leonardo da Vinci found an original way to listen to underwater sounds. For this, he suggested using a paddle dipped in water. If we compare the speed of sound in air (331 m / s) and in water (1435 m / s), we can trace the clear advantage of a denser medium for its propagation.
Solids break all records. The speed of sound propagation in them can reach 5000 m / s. An interesting experience can be done with an ordinary rail by putting an ear to it. If someone in the distance hits him with a hammer, then we can clearly hear two blows. The first is the sound information obtained by propagating through the metal, and the second is the wave that arrived through the air.
For a huge number of physical phenomena, the speed of sound is a kind of standard, a starting point for comparison. Modern fighters consider their supersonic abilities the greatest achievement. By measuring the transit time of a certain section of the sound wave, you can determine the distance with fairly high accuracy.
The use of sound effects in various fields of human activity is striking in its diversity.