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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?

蠟燭的火焰到底是由什麼組成的?

字幕與單字

B1 中級 中文 火焰 離子 蝴蝶 電場 導電 空氣

What's In A Candle Flame?

  • 37 0
    林宜悉   發佈於 2020 年 03 月 28 日
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