We define sound as vibrations that travel through the air or another medium and can be heard when they reach a person’s ear. However, sound does more than convey noises for one to hear; it helps us sleep, helps us see, and helps us put out fires. Keep reading to learn more about these fascinating scientific facts.
Sound Extinguishes Fire
For over a century, scientists have known that noise can extinguish flames. The first known documentation of the discovery is linked to Heinrich Rubens, a German physicist who researched this sound capability around 1905. Scientifically speaking, since sound travels in waves, they exist due to slight changes in velocity. These changes create high-pressure and low-pressure zones, and sound travels through these zones to become the noise we hear. Pressure is also correlated with temperature, which can be seen in the ideal gas law. By forcing fire into an environment in which it will encounter low-pressure zones, and therefore lose pressure, a subsequent temperature drop occurs. Scientists have harnessed this powerful fact several times; the Defense Advanced Research Projects Agency (DARPA), the government branch that develops state-of-the-art technologies for the American military, constructed a heavy-duty sound-based fire extinguisher in 2008. Shortly afterward in 2017, two George Mason University students engineered a similar extinguisher on a smaller scale.
The sound-based fire extinguisher created by two college students.
Many of you have most likely heard of white noise, defined as a heterogeneous mixture of sound waves extending over a wide frequency range. It is known to help people fall asleep because of said frequency range; the variety masks other variations in sound from a person’s surroundings, thereby effectively squashing all potential distractions for light sleepers. However, to some people, white noise creates a constant disturbance, despite the fact that it covers several others. In this case, one can seek out the fraternal twin of white noise: pink noise. In white noise, the power per hertz remains at the same level regardless of changes in frequency. In contrast, the power per hertz in pink noise differs with frequency, which changes less randomly than in white noise. As the intensity raises and diminishes, pink noise maintains a consistent level of energy. Pink noise is linked to creativity, concentration, and productivity. It also regulates brain waves, lengthens cycles of deep sleep, and improves memory. Examples can be found in rainfall and fans, while white noise is closer to television static in frequency and effect.
How Sound Helps Us See
In the absence of one sense, sometimes one of the remaining four becomes more sensitive and useful. Researchers have confirmed the opposite this in the relationship between sight and sound. A group of scientists created a study in which monkeys were tested on their ability to find a panel when it had a light on it versus when it was dimmed. In a silent, darkened environment, the monkeys had difficulty finding the panel, but when scientists played a short noise near the dimmed panel, the test subjects found it almost instantly. This result led scientists to believe the previous hypothesis that the visual and auditory parts of the brain did not meet was incorrect; since the monkeys acted as if someone illuminated the panel just because of a sound, the experiment conductors discovered the interactions between the aforementioned parts of the brain in “emergency” situations.
Quite simply, noise surrounds us. As one can see, however, sound does more than translate our favorite music or allow us to hold conversations aloud. These three examples, along with many others from this field of science and others continue to show how truly powerful and thoughtful God’s creation is.
Did you learn anything new from this article? Do you know of any other crazy sound-related discoveries? Let us know in the comments!
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