Right now, the most common use humans make of sounds is to communicate, emitting sounds through the mouth in a specific way to create words. These same words can be used in everyday conversations or to sing songs. Music could also be considered another form of communication, only a little more artistic, as it includes sounds emitted by musical instruments of all kinds, creating a melody that tries to convey feelings and ideas.
Sound has always been an important part of technology, since the 19th century when the first phonograph was created, a very primitive radio system was patented, or when the first telephone that transmitted voices was built. During the twentieth century there were a number of impressive advances, making both telephone and radio a common technology and accepted by society, but also including other fabulous improvements, such as televisions (which also emitted images, along with sound), stereo sound and the ability to make audio recordings on cassettes, CDs, and digitally with the appearance of MP3 files. Find out more with us at Seksuroba.
In spite of all these milestones in technology, where sound was the protagonist, when we think about what the future will be like, we never imagined that great advances could be made in the area of acoustics. However, right now, science is using sound to create things that are cooler than ever, and that may become more common in the future.
A group of researchers at Penn State University in the United States have developed a refrigerator that works with sound. It operates on the principle that sound waves compress and expand when there is air around them, causing them to both heat and cool, creating a kind of gas. For this to work and replace the electricity currently used by these appliances, enough of the gas produced by the sound waves needs to be placed inside the cooling chamber. In this case, they decided to put the equivalent of 10 atmospheres of earth gas. Once inside the chamber, the gas is pressed with more than 173 decibeles of sound (which would be worse than sitting inside a running turbine of an airplane), producing heat. Then, the heat is absorbed by metal plates that take it to a changing system where it is removed, creating cold inside the refrigerator.
Although it sounds somewhat complicated, its application would be a simple solution to create models of refrigerators much more “green” than any other existing in the current market. Now we find refrigerators that save energy, but still use chemical refrigerants that damage our atmosphere.
We already know that the life of smartphone batteries is terrible, so wouldn’t it be great to be able to charge them easily, without having to rely on ordinary electricity at all? Maybe someday it can be done using only your voice. Sound, as we said before, is a viable source of energy because it produces heat and some researchers have been experimenting with this so that you can charge your mobile thanks to the emission of sound produced by your voice every time you make a call.
During 2011, scientists in Seoul put nano-zinc oxide bars between two electrodes, a perfect and very small system for generating electricity using sound waves. This produced just 50 millivolts, which is too little energy to charge any mobile phone. By 2014, however, other scientists in London used the same method and managed to produce five volts, enough to charge a smartphone. Is this a real alternative that we can use in the future?
Disney is not only dedicated to creating fantastic princesses, it also brings important science to the world, as is the case of the “Ishin-Den-Shin” project, a Japanese expression used when there is communication through mutual and tacit understanding. This project has an interesting system for transmitting sounds that consists of connecting a microphone to a computer so that someone can speak through it. The computer then converts it into a loop recording and sends it back into the microphone through a thin wire, but now it is not a sound but a high voltage, low current signal that is totally inaudible. The signal, in turn, creates an electrostatic field that produces a very small vibration when the finger of the person holding the microphone touches an object, turning the person into a loudspeaker.
Since all this sounds a little complicated, let’s go to the coolest part of the system: when person A is holding the microphone in one of his hands, he can use one of his fingers on the other to touch the ear of person B, who will feel a small vibration. The moment of touch creates a loudspeaker between the two individuals.