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  • Last week, a senior vice president of Google quietly parachuted from 135,890 feet, breaking

  • the sound barrier in the process. How is it that a human can fall faster than sound?

  • Hey guys, Amy here for DNews, and to call the sound barrier a “barrieris actually

  • a bit of a misnomer.

  • Anything moving through the air, like an airplane, has to push air molecules out of its way to

  • move. This forms a pressure wave in front of and behind the airplane, and the faster

  • that airplane flies the faster those molecules have to move out of the way. The pressure

  • waves start to compress. At a certain point, the molecules can’t get out the way fast

  • enough and. They form a “barrierin front of the airplane that also compresses the pressure

  • wave into a single shock wave that moves at the speed of sound, commonly called Mach 1.

  • When the airplane goes faster than the speed of sound it pierces through that barrier created

  • by the built up shock wave, creating a negative pressure space around it. The sonic boom is

  • the sound associated with the sudden change of pressure.

  • Engineers worked long and hard to get a plane to fly through the so-called sound barrier

  • and go supersonic in level flight in the 1940s; for years pilots trying to fly faster than

  • sound had airplane shake and break apart around them thanks to those pressure waves. It was

  • Chuck Yeager piloting the X-1, which was designed to look and fly like a bullet, who first broke

  • through that invisible wall in the sky.

  • So how can a human make it through the sound barrier without a perfectly aerodynamic rocket-powered

  • airplane?

  • There’s more to going supersonic than just speed. Altitude, and specifically the thickness

  • of the atmosphere at different altitudes, is a major factor. The higher the altitude

  • the thinner the atmosphere, which means there are fewer air molecules for a plane, or a

  • body, to get out of the way.

  • Because extreme parachute jumpers like Felix Baumgartner and Alan Eustace jumped and free

  • fell from such high altitudes, it was easier for them to move air molecules out of the

  • way to hit Mach 1 because the air is less dense. Baumgartner didn’t need rockets to

  • break through the sound barrier falling from more than 127,000 feet. Yeager, flying the

  • X-1 at 43,000 feet, on the other hand, did need a rocket boost. But interestingly, Baumgartner’s

  • supersonic moment required just 10 miles per hour less than Yeager’s.

  • And, of course, specialized pressure suits these jumpers wore play a big part. Suits

  • designed to protect the wearer from the shock waves associated with the sound barrier, even

  • in less dense air, are vital to success. And not to mention survival.

  • So what do you guys think. Would you make a supersonic jump?

  • Let us know in the comments below and don’t forget to subscribe for more DNews every day

  • of

  • the week.

Last week, a senior vice president of Google quietly parachuted from 135,890 feet, breaking

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突破音障你能活下來嗎? (Can You Survive Breaking The Sound Barrier?)

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    羅紹桀 發佈於 2021 年 01 月 14 日
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