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• Recently some friends of mine went to the Gordon dam in Tasmania

最近我朋友去了塔斯馬尼亞島的戈登大壩

• which is a hundred and twenty-six and a half meters or four hundred and fifteen feet high.

有126.5公尺或415尺高

• then they drop a basketball over the edge.

然後他們從邊坡丟下一顆籃球

• you can see that the basketball get pushed around a bit by the breeze.

你可以看到籃球被風吹的搖搖晃晃

• but it lands basically right below where it was dropped.

但你可以看到它掉到地面的地方大致就是當初丟下的地點

• Now watch what happens when they drop another basketball.

現在來看看當他們丟下另一顆籃球會發生什麼事

• This time with a bit back spin.

這次加一點向後旋的力

• wow! where will it go? hahaha (It's incredible!)

哇！它會跑去哪？哈哈哈(真不可思議！)

• So you want us to get back in the water, do you?

所以你想要我們去水裡拿那顆球是嗎？

• This is Brad who just threw it.

• I literally just dropped it with a bit spin like I didn't even throw it.

嚴格說起來我只是丟下的時候施一點旋轉的力但並沒有用"丟"的

• and I just took off. I have no idea that I'm gonna do that.

然後我就放手了，我根本沒有想到我會那樣做

• And this is where I come in. The basketball with subject to the magnus effect

我從籃球(實驗)中了解到這就是馬格納斯效應

• which affects all rotating balls are cylinders as they fly into the air

它會影響那些在空中飛且旋轉的圓球

• and it works like this.

運轉的方式如下

• as the basketball picks up speed, air on the front side of the ball is going in same direction as it's been.

當籃球運轉的速度增加時，迎面的氣流和籃球的旋轉有著相同的方向

• and therefore it gets dragged along with the ball and deflected back.

因此這氣流被球影響而往後傾斜

• Air on the other side is moving opposite to the ball spin

另外一邊上層的的氣流和籃球旋轉的方向恰好相反

• so the flow separate from the ball instead getting deflected.

所以籃球兩側的氣流有不同的方向而非一致

• The net result is the ball pushes air one way so the air applies in equal force in a ball the other way.

結果使得籃球會推著一邊的氣流，而另一邊的氣流被同樣的力道推進著

• and this is known as the Magnus effect named after Heinrich Gustav Magnus who described it in 1852

這就是海因里希·古斯塔夫·馬格努斯在1852年所記下的「馬格納斯效應」

• of course Isaac Newton beat him to it by nearly two hundred years describing the flight of tennis balls at Cambridge College

理所當然地，艾薩克·牛頓兩百年後在劍橋大學時對網球的飛行的描述推翻了這項論點

• but you know he's got enough stuff named after him.

但你知道已經有太多事物是以牛頓的名字命名

• This effect is very important in sports like tennis, soccer and golf

這個效應對各式的球類都有想當重要的影響，譬如網球、足球和高爾夫球

• but could it have non-sport applications?

但它有可能運用在不是球類的運動上嗎？

• Perhaps this is a sailboat. I know it doesn't look like a sailboat but those aren't chimneys

可能能運用在帆船上。我知道那看起來不像帆船，但也不是煙囪

• they are spinning cylinders called flettner-rotors and they take the place of the sails.

那是旋轉的圓筒稱作Flettner-rotor弗萊特納補翼，用來取代風帆

• They deflect crosswinds using the Magnus effect to propel the ship forwards

他們透過馬格納斯效應去使橫風傾斜進而帶動船前進

• In this, it's a plane with spinning cylinders instead of wings

在飛機裡的是旋轉的汽缸而不是機翼

• using the Magnus effect the cylinders actually generate more lift than traditional wings

靠著馬格納斯效應這個汽缸比起傳統的機翼能夠產生更多的轉速

• however they also generate way more drag making them impractical.

然而也產生了更多的拉力，使其不實用

• this plane only flew once and then it crashed

這飛機只能飛一下下就會墜落

• but a man is in fact is making a comeback

但有位男子事實上將它改良

• here's an experimental rotor wing aircraft which generates all its lift from spinning cylinders

這是個實驗性轉軸型機翼的飛機，靠著旋轉的汽缸能夠產生最大的轉速

• and this is the E-ship 1 which uses four spinning cylinders that is four flettner rotors

這個E-ship 1是用四個旋轉的汽缸也就是四個弗萊特納補翼

• to increase its efficiency and reduce the amount of diesel

去增加它的效率並減少柴油的使用量

• so in the future, the Magnus effect may help more than just basketballs' fly.

因此在未來馬格納斯效也許能協助更多籃球飛行

• Oh, where will it go?

哇，它會跑去哪？

Recently some friends of mine went to the Gordon dam in Tasmania

B1 中級 中文 美國腔 籃球 氣流 丟下 效應 機翼 轉速

# 把球從水庫丟下去後，沒想到球竟然...(Surprising Applications of the Magnus Effect)

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Claire Chi 發佈於 2015 年 07 月 24 日