中級 美國腔 340 分類 收藏
開始影片後,點擊或框選字幕可以立即查詢單字
字庫載入中…
回報字幕錯誤
If you don't know about grapes in the microwave, you haven't been keeping up with the internet.
"All right, so we're going to do this grape in a microwave experiment."
For 20 years, people have been microwaving two grape halves connected by a bridge of skin to create sparks, light, plasma!
"Well, there's a lot of juice from these, actually."
A plasma is a superheated gas in which electrons have been stripped from the molecules.
Lightning is a common example.
So how do you get that from grapes?
Amateur explanations focused on conducting electricity between the two halves.
The skin bridge was the key.
Or was it?
Scientists who have now investigated the grape plasma phenomenon in depth say, "no, you can use two whole grapes as long as they touch each other."
(And the) explanation has to do not with conductivity, but with microwaves being trapped inside each grape.
Here's what happens.
The wavelengths of microwave radiation are about five inches.
But water, which is what grapes are made of, compresses these wavelengths to about a half an inch.
That's about the same size as the grape.
So the microwave radiation bounces around inside the grape and concentrates in the center.
That's called resonance.
With two grapes, or two spheres of a hydrogel — mostly water, but no skin — the concentration is where the two meet.
There's such a strong electromagnetic field at that spot that it sparks a plasma by stripping an electron off a sodium or potassium molecule.
That triggers a cascade of other atoms in the air, losing electrons as they absorb microwave radiation.
(But) that's not what really excited the scientists.
They were interested in the hot spots where the grapes meet.
You can see them in red.
Microwaves in that region were about 80 times smaller than in air.
That was a real surprise to the scientists because water worked on microwaves in a way that had never been seen.
Now if a substance could be found that would do that with visible light, which is so small it's measured in nanometers, that could have great implications for microscopes, research in computer chips and other areas.
So never assume a party trick is just a party trick, not if it involves a microwave.
"O.K., that was awesome."
提示:點選文章或是影片下面的字幕單字,可以直接快速翻譯喔!

載入中…

別把葡萄放微波爐,除非你想生火 (Why Microwaved Grapes Explode! | ScienceTake)

340 分類 收藏
April Lu 發佈於 2019 年 3 月 11 日    Arnold Hsu 翻譯    Evangeline 審核
看更多推薦影片
  1. 1. 單字查詢

    在字幕上選取單字即可即時查詢單字喔!

  2. 2. 單句重複播放

    可重複聽取一句單句,加強聽力!

  3. 3. 使用快速鍵

    使用影片快速鍵,讓學習更有效率!

  4. 4. 關閉語言字幕

    進階版練習可關閉字幕純聽英文哦!

  5. 5. 內嵌播放器

    可以將英文字幕學習播放器內嵌到部落格等地方喔

  6. 6. 展開播放器

    可隱藏右方全文及字典欄位,觀看影片更舒適!

  1. 英文聽力測驗

    挑戰字幕英文聽力測驗!

  1. 點擊展開筆記本讓你看的更舒服

  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