exploded and to this day remained the only use of nuclear weapons for warfare, but with around

因而成為至今唯一用於實戰的核武器，

15,000 warheads remaining in the world

但是全世界卻有 15,000 枚核彈頭，

What happens if we have a nuclear war? The impact of a single nuclear bomb depends on many factors like the weather, weapon design,

如果發生核戰，會發生什麼事？ 核彈的影響力由許多因素決定，如：天候、武器設計

geographical layout of where the bomb hits and if it explodes in the air or [on] the ground. Approximately

被核彈命中的地理環境、以及核彈是在空中、地表或地下，

35 percent of the energy comes in the form of thermal radiation or heat

約 35% 的能量來自熱輻射或熱能

since thermal radiation

熱輻射會以亞光速前進

Travels at approximately the speed of light the flash of light and the heat comes several seconds before the blast wave and this causes flash

在爆炸之前的幾秒內，就會出現光和熱，任何在此時觀看爆炸的人

Blindness to anyone looking a temporary blindness of a few minutes with a one megaton bomb which is 80 times larger than the hiroshima bomb

都會產生光盲視（flash Blindness），一種長達幾分鐘的暫盲。一枚百萬噸級核彈威力（廣島原子彈的 80 倍

but much smaller than many modern nuclear weapons those 21 kilometers away would experience flash blindness on a clear day and

但是這遠小於多數現代核彈）可以在晴朗的白天對 21 公里遠的人造成光盲視

Even up to 85 kilometers away on a clear night

在晴朗的夜晚則甚至能達到 85 公里遠。

Thermal radiation burns happen closer to the bomb with first-degree burns occurring around 11 kilometers

熱輻射燒燙傷在 11 公里內可以造成一級燒燙傷。

Second-degree burns at 10 kilometers and third-degree burns destroying skin tissue at 8 kilometers third-degree burns that cover over

10公里內造成二級燒燙傷。能破壞體表皮膚組織的三級燒燙傷則在8公里範圍內，

[24%] of the body will likely be fatal without quick medical care these distances are variable depending on the weather and what clothing you're wearing

[24%] 的三級燒燙傷在沒有醫療急救下可能是致命的。它的程度將取決於當日天氣與你所穿的衣服。

White clothing for example can reflect some of the energy well darker clothes absorb it at its [center] the hiroshima explosion was estimated to be

例如白衣服能反射多數能量，黑衣服則會吸收它。

[300,000] degrees Celsius which is over

在廣島爆炸的中心，溫度會達 [300,000] °C。

300 times hotter than the temperature bodies are cremated at this intense heat

這等同於焚化屍體之溫度的 300 倍。

Reduces a body to its basic elements the radiation from the blast also behaves like sunlight

如此強烈的熱能會將人身還原成基本元素，輻射爆炸的表現也如太陽那般。

So [object] cast shadows where the radiation doesn't directly hit

所以 [物體] 會在輻射不直接撞擊的地方留下投影。

But most of the energy released in the nuclear explosion is in the blast which drives air away from the site of the explosion

但是核爆釋放的大部分能量都是驅散現場空氣的爆炸風

creating a sudden change in air pressure

這造成空氣壓力急遽變化

That can crush objects or knock them down [if] we use a [1] megaton bomb as an example again within a 6 kilometer radius

那將可以粉碎或擊倒物體。 [而如果] 我們以 [一] 枚百萬噸級炸彈為例，在半徑六公里內的物體

There would be an estimated

會受到相當於 180 噸的力量以

180 tons of Force on the wall of Every two-story building with wind speeds of

時速 255 公里的風速撞擊一棟二層樓房

255 kilometers an hour within a 1 kilometer radius the peak pressure is four times greater and wind speeds reached

半徑 1 公里內達到的最大壓力為風速的四倍

756 kilometers an hour the human Body can endure this amount of pressure

亦即時速 756 公里，人體雖然可以承受這樣的壓力

However the winds would create fatal collisions with nearby objects

但是風會導致附近物體產生致命性的碰撞

So deaths would largely be from collapsed buildings all this at one megaton compare that with the largest nuclear bomb ever detonated

因此死因主要會來自建築物的倒塌。 而比起百萬噸，過去引爆過的最大噸級核彈

the 50 megatons Tsar bomba dropped on an isolated Island in Russia, and you're looking at

50 百萬噸的沙皇核彈是落在俄羅斯的一座孤島上，

3333 Hiroshima bombs combined if you happen to survive all this now you have to worry about radiation

此時你所看到的是 3333 枚廣島原子彈的總和。 如果你恰巧在此倖存下來，現在你必須擔心輻射

Now not all radiation is harmful. We're exposed to different forms of radiation every day like our phones

但不是所有輻射都是有害的， 我們每天會接觸不同形式的輻射，如我們的手機

But ionizing radiation at the center of a nuclear bomb has enough energy to rip electrons from atoms

但是核彈中心的電離放射有足夠能量將電子從原子中拉扯出來。

But the amount of radiation you encounter is greatly affected by whether you're outside?

但是你所遭遇的輻射量非常的受到你的人是在室外或

or inside in a wooden structure or a cement structure and so on

是在木造結構或水泥結構的室內諸如此類的條件影響、

exposure to 600 rem Radiation has a [90] [percent] chance of creating fatal illness while a dose of

暴露於 600 雷姆輻射將有[百分之][90]的機率造成致命疾病，

450 rem is estimated to create a fatal dose within half of those affected, but even those who recover still suffer long-term

據估計，450 雷姆是致命死亡估計量的一半。 但是那些痊癒的人也仍會受到長期性傷害

molecular bonds and strands of Dna are broken and while most repair around a corridor don't which can result in future genetic mutations and

DNA分子鍵和分子鏈被破壞，雖然大多數可修復，

increased probability of cancer

也不會導致未來基因突變和癌症的機率增加。

Then there is the fallout

接著是[Fallout]。

When a bomb is detonated on or near the surface of the Earth the blast creates a crater and the material that used to be

當一枚炸彈在地表或近地爆炸時，爆炸會產生一個彈坑，並且把該處的沉積物汽化並帶入空中，

Deposited in the crater is carried up [into] the air as vaporized dirt particles forming the familiar mushroom cloud these particles become radioactive

便形成了你我熟悉的蘑菇雲，而這些顆粒會具有放射性

And eventually condense and come back down as fallout

並且在冷凝後作為沉降物回到地表

depending on wind conditions

依據風力條件，

Radioactive fallout can travel for hundreds of miles and though it can fall in the form of black rain for the most part you can't

輻射塵可以飛行長達百公里， 雖然它可以以黑雨的形式出現，

detect fallout with your senses luckily fallout radiation

但是大部分時候你無法自己察覺這些輻射。幸運的是

Decays Fairly quickly and within two weeks material will have declined to about 1% of its initial radiation level

輻射塵的輻射衰變相當迅速， 它在兩周內會就降至初始輻射的百分之 1

But you would have to stay in a shelter

但是你將得待在庇護所裡直到它結束。

Until then so what is a Multi bomb Nuclear war broke out a recent study?

那麼如果爆發核戰爭的話呢？最近一項研究假設

Imagined what 100 detonated warheads the approximate size of a her ocean bomb would look like if India and Pakistan went to war

如果引爆 100 枚尺寸相似廣島原子彈的彈頭，這會如同是印度和巴基斯坦戰爭。

These two nations have relatively small stockpiles of weapons

相對於美俄、中國等國家，

Compared to countries like the us Russia and China however this would still do huge damage

此二者的武器儲備量較低，但是這仍然會造成巨大的損失

after the Nuclear Exchange 5 megatons of [Blackrock] would immediately enter the atmosphere

經歷過互相核打擊之後，5 百萬噸的「黑石」將立刻進入大氣層

Causing global temperatures to fall and receive 9% less rain annually, [though]

將使全球氣溫下降，並且每年減少 9% 降雨量．[儘管]

these changes sound small they could be enough to Trigger crop failures and famine a

儘管這變化乍聽很小，卻足以觸發農作物欠收與飢荒

separate study estimated two billion people would starve in the wake of a

一項獨立研究估計，20 億人將在100枚核彈的戰爭中一夜陷入飢荒

100 a bomb war so what should you do we created a video called how to survive a nuclear war that looks into strategies for

所以你應該怎麼做？ 我們製作了一部叫「如何在核戰中生存」的影片，

Safety in the event of a nuclear bomb near you which you can click on here to check out

教你如何在即便核彈是落在你附近的情況下生存，你可以點即此來觀看

Don't forget to [subscribe] for more weekly science videos every Thursday and click that bell to make sure you get notifications for our videos

別忘了訂閱以收看固定每周四的科學影片，並且點擊鈴鐺以確保你會收到我們影片的通知

We'll see you next week

下周見。