Name: 一番音が大きいのは？ (What's The Loudest Possible Sound?)
Uploaded: 2021-01-14T06:50:15.000Z
Duration: 4 min 8 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

再帰代名詞

If I had a machine that allowed me to suddenly… transport myself elsewhere, the air filling

the vacuum where I used to be would collapse with enough force it would burst the eardrums

and cause nausea in anyone standing nearby.

Teleportation may sound like a cool idea, but thanks to sound itself, it's a pretty dangerous proposition.

A sound wave is mechanical, it needs a medium to travel through.

Right now, the wave created by my voice is wiggling the air back and forth, creating

When we talk about how loud a sound is, we’re really talking about the intensity of that

pressure wave. The louder the sound, the more intense the wave.

Unlike ripples on a pond, sound moves out from its source in the shape of a sphere.

Just like a bubble gets thinner as it gets bigger, the farther we are from the source

of a sound, the less pressure there is on a given area of the sound sphere.

This means that if we move twice as far from a sound, it will be at one-fourth the intensity.

The smallest sound pressure wave we can hear vibrates our eardrum less than the width of

a single oxygen molecule! Yet we can comfortably hear sounds a billion times more intense.

Hearing has the widest range of any of our senses, by far, so we need a wide scale to

dBs are logarithmic. Something 10 decibels louder is ten times as intense. 30 decibels?

A thousand times as intense. Our threshold for pain comes at sounds 10

trillion times more intense than the quietest sound we can hear.

In 1883, the island of Krakatoa in the South Pacific erupted, sending ash nearly 17 miles

into the atmosphere, with a force four times more powerful than the Tsar Bomba, the most

powerful nuclear weapon ever detonated. At nearly 180 dB, this explosion shattered

eardrums 40 miles away, and pushed a wave of air around the globe four times.

Imagine hearing this… BANG! only three thousand miles away. Get close

enough to that, and it'll be the last sound you never hear.

But there’s an upper limit to how loud a sound can be, and, hint: It’s not “11”.

Sound waves push air together at their peak, and leave low pressure in the valleys. Once

this part reaches a vacuum, the sound can’t get any louder. Push the wave any harder than

194 dB, then it distorts, heats up, it’s moving faster than the speed of sound.

We can go higher, only then it's stopped being sound and has become a shock wave.

NASA’s Saturn V rocket was capable of shooting out 7.5 million pounds of space-fire thrust

at 200-220 dB. That’s enough pressure to ignite grass a kilometer and a half away and

kill everything within a few hundred meters.

For Space Shuttle launches, NASA dumped water at a rate of 900,000 gallons per minute into

a pool underneath the launch pad to keep the sound waves from literally ripping the shuttle

Of course, planets with more dense atmospheres, like Venus or Saturn, could sustain more intense

sound waves, and even higher decibel levels.

It makes me wonder, what would a lightning storm on Saturn sound like?