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Inside the world's quietest room
If you stand in it for long enough, you start to hear your heartbeat. A ringing in your ears becomes deafening. When you move, your bones make a grinding noise. Eventually you lose your balance, because the absolute lack of reverberation sabotages your spatial awareness.
In this room at Microsoft's headquarters in Redmond, Washington, all sound from the outside world is locked out and any sound produced inside is stopped cold. It's called an anechoic chamber, because it creates no echo at all — which makes the sound of clapping hands downright eerie.
The background noise in the room is so low that it approaches the lowest threshold theorized by mathematicians, the absolute zero of sound — the next step down is a vacuum, or the absence of sound.
This is the world's quietest place.
Deafening silence
The room offers a very rare sensorial experience.
As soon as one enters the room, one immediately feels a strange and unique sensation which is hard to describe, wrote Hundraj Gopal, a speech and hearing scientist and the principal designer of the anechoic chamber at Microsoft, in an email. Most people find the absence of sound deafening, feel a sense of fullness in the ears, or some ringing. Very ____ sounds become clearly audible because the ambient noise is exceptionally low. When you turn your head, you can hear that motion. You can hear yourself breathing and it sounds somewhat loud, he said.
In the real world, Gopal explained, our ears are constantly subject to some level of sound, so there is always some air pressure on the ear drums. But upon entering the anechoic room this constant air pressure is gone, since there are no sound reflections from the surrounding walls.
This is a novel experience, he wrote. [...]
Jacopo Prisco, CNN
Disponível em: <https://edition.cnn.com/style/article/ anechoic-chamber-worlds-quietest-room/index.html>. Acesso em: 29 mar.2018.
Choose the option in which the pair of words from the text, formed with the suffix ing, represents a verbal form.
