B2 中上級 2928 タグ追加 保存
動画の字幕をクリックしてすぐ単語の意味を調べられます!
単語帳読み込み中…
字幕の修正報告
Sometimes when a fish is reeled up to the surface
it will appear inflated,
with its eyes bulging out of their sockets
and its stomach projecting out of its mouth,
as if its been blown up like a balloon.
This type of bodily damage, caused by rapid changes in pressure,
is called barotrauma.
Under the sea, pressure increases by 14.7 pounds per square inch
for every 33 foot increase in depth.
So, take the yelloweye rockfish,
which can live as deep as 1800 feet,
where there's over 800 pounds of pressure on every square inch.
That's equivalent to the weight of a polar bear balancing on a quarter.
Now, Boyle's gas law states
that the volume of a gas is inversely related to pressure.
So, any air-filled spaces, like a rockfish's swim bladder,
or human lungs,
will compress as they descend deeper
and expand as they ascend.
After a fish bites a fisherman's hook and is quickly reeled up to the surface,
the air in its swim bladder begins to expand.
Its rapid expansion actually forces the fish's stomach out of its mouth,
while the increased internal pressure pushes its eyes out of their sockets,
a condition called exophthalmia.
Sometimes rockfish eyes will even have a crystallized appearance
from corneal emphysemas,
little gas bubbles that build up inside the cornea.
Thankfully, a scuba diver doesn't have a closed swim bladder to worry about.
A diver can regulate pressure in her lungs by breathing out as she ascends,
but must be wary of other laws of physics that are at play under the sea.
Henry's law states that the amount of a gas that dissolves in a liquid
is proportional to its partial pressure.
The air a diver breathes is 78% nitrogen.
At a higher pressure under the sea,
the nitrogen from the air in a scuba tank
diffuses into a diver's tissues in greater concentrations than it would on land.
If the diver ascends too quickly,
this built up nitrogen can come out of solution
and form microbubbles in her tissues, blood and joints,
causing decompression sickness, aka the bends.
This is similar to the fizz of carbon dioxide coming out of your soda.
Gas comes out of solution when the pressure's released.
But for a diver, the bubbles cause severe pain
and sometimes even death.
Divers avoid falling victim to the bends by rising slowly
and taking breaks along the way, called decompression stops,
so the gas has time to diffuse back out of their tissues
and to be released through their breath.
Just as a diver needs decompression,
for a fish to recover, it needs recompression,
which can be accomplished by putting it back in the sea.
But that doesn't mean that fish should just be tossed overboard.
An inflated body will float
and get scooped up by a hungry sea lion or pecked at by seagulls.
There's a common myth
that piercing its stomach with a needle will let air escape,
allowing the fish to swim back down on its own.
But that is one balloon that shouldn't be popped.
To return a fish properly to its habitat,
fisherman can use a descending device instead
to lower it on a fishing line and release it at the right depth.
As it heads home and recompression reduces gas volume,
its eyes can return to their sockets and heal,
and its stomach can move back into place.
This fish will live to see another day,
once more free to swim, eat, reproduce and replenish the population.
コツ:単語をクリックしてすぐ意味を調べられます!

読み込み中…

【TED-Ed】The effects of underwater pressure on the body - Neosha S Kashef

2928 タグ追加 保存
稲葉白兎 2015 年 4 月 14 日 に公開
お勧め動画
  1. 1. クリック一つで単語を検索

    右側のスプリクトの単語をクリックするだけで即座に意味が検索できます。

  2. 2. リピート機能

    クリックするだけで同じフレーズを何回もリピート可能!

  3. 3. ショートカット

    キーボードショートカットを使うことによって勉強の効率を上げることが出来ます。

  4. 4. 字幕の表示/非表示

    日・英のボタンをクリックすることで自由に字幕のオンオフを切り替えられます。

  5. 5. 動画をブログ等でシェア

    コードを貼り付けてVoiceTubeの動画再生プレーヤーをブログ等でシェアすることが出来ます!

  6. 6. 全画面再生

    左側の矢印をクリックすることで全画面で再生できるようになります。

  1. クイズ付き動画

    リスニングクイズに挑戦!

  1. クリックしてメモを表示

  1. UrbanDictionary 俚語字典整合查詢。一般字典查詢不到你滿意的解譯,不妨使用「俚語字典」,或許會讓你有滿意的答案喔