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• What is a candle flame really made of?

蠟燭的火焰到底是由什麼組成的?

• I am at the Palace of Discovery in Paris to do an experiment

我在巴黎的"發現宮"博物館

• that beautifully demonstrates the answers.

參與了一個巧妙的實驗來找出答案。

• Ok so we're turning on an electric field here

我們要讓這塊金屬板帶負電

• and we see that the flame is spreading out.

在靜電感應的作用下

• Thats very cute,

另一邊的金屬板將會帶正電

• it's like a butterfly.

然後我們打開電源

• And you can see that the flame

你可以看到火焰因為金屬板之間的電場而變形了

• has two separate pieces to it now.

這電壓有幾伏特?

• One is going towards the negative plate.

大概是...

• Those would be the positive ions,

20,000 伏特

• and the negative ions will be going towards a positively charged plate.

你有看到蝴蝶嗎?

• So we see the flame kinda flattening out.

蝴蝶?

• But if that didn't convince you

像蝴蝶，火焰這樣子動

• that flame contains ions,

看起來就像像蝴蝶拍動翅膀

• then check part two of our experiment

火焰就像蝴蝶，真可愛

• where we compare the conductivity of a

火焰是一種電漿

• flame to the connectivity of air,

也就是一團帶電離子

• which is normally a pretty good insulator.

你可以看到火焰分離成兩部分

• It requires about 10,000 volts

火焰中的負離子靠向正電極，正電離子則靠向負電極

• to break down a centimeter of air.

所以火焰看起來被拉成扁平的

• So right now this plate is is about 20,000 V.

如果這還不足以說服你火焰中含有帶電離子

• You see that the spark is only little,

在第二部分的實驗中，我們將比較火焰和空氣的導電性

• but if I put it around the flame,

一般來說，單純的空氣導電能力很差

• we will see if we can get a bigger spark happen.

讓1公分寬的空氣通電，大概需要10000伏特

• Look at that, yeaaa!

所以現在這組電極大概是10000伏特

• Because the flame has those ions in it,

電弧看起來不大

• that means that we can break down

但如果我們把火焰放在電極中間

• a greater distance of air.

電弧就能變長許多

• This greater conductivity.

你看看

• It's awesome! You love doing this, right?

因為火焰中帶有離子

• A strong enough electric field

離子提高了空氣的導電能力，所以我們能用相同的電壓，讓較長距離的空氣導電

• can actually extinguish the flame

真是太有趣了，你也很愛玩這個對吧

• but watch carefully what happens when the flame goes out.

是啊

• Just like in the flame, the opposite charges in the smoke

夠強的電場甚至可以把火焰熄滅

• are pulled in opposite directions.

仔細看看火焰熄滅的過程

• Now while some may argue that a flame is not

你看

• truly a plasma because it's not hot enough

煙裡有離子存在嗎?

• and it doesn't have a high enough density of ions,

當然有

• one thing is for sure, it does contain ions

就像火焰，煙裡正負相反的離子

• which have important electrical properties,

也被電場拉向相反的方向

• which can be demonstrated if you have a strong enough electric field.

有些人認為，煙不能算是電漿

What is a candle flame really made of?

B1 中級 中文 火焰 離子 蝴蝶 電場 導電 空氣