The science of static electricity - Anuradha Bhagwat

靜電的科學 - Anuradha Bhagwat

譯者: Eddy Chang 審譯者: Marssi Draw

It can strike without warning, at any moment.

在任何時候都有可能無預警的被電到

You may be walking across a soft carpet and reaching for the door knob

你可能正踩過軟毛地毯 然後要去拉門把

when suddenly...zap!

突然…觸電了！

To understand static electricity,

要了解靜電是什麼

we first need to know a bit about the nature of matter.

首先我們需要了解物質的自然特性

All matter is made up of atoms

所有物質都是由原子構成

that consist of three types of smaller particles:

原子則是由三個小部分所組成的

negatively charged electrons,

帶負電的電子

positively charged protons,

帶正電的質子

and neutral neutrons.

以及不帶電的中子

Normally, the electrons and protons in an atom balance out,

通常一個原子裡的電子與質子會抵銷

which is why most matter you come across is electrically neutral.

因此大部分你遇見的物質都不帶電

But electrons are tiny and almost insignificant in mass,

不過電子很微小，而且幾乎微不足道

and rubbing or friction can give loosely bound electrons

經過搓揉或磨擦後 可以讓鬆散的束縛電子

enough energy to leave their atoms and attach to others,

有足夠能量脫離它們的原子 然後附到其他原子上

migrating between different surfaces.

在不同的表面間相互遷移

When this happens,

當這個情況發生時

the first object is left with more protons than electrons

原先物體留下的質子多於電子

and becomes positively charged,

這個東西就變成帶正電

while the one with more electrons accumulates a negative charge.

另一物體則累積較多電子 而變成帶負電

This situation is called a charge imbalance,

這個情況稱為電荷不平衡

or net charge separation.

或淨電荷分離

But nature tends towards balance,

不過自然界傾向維持平衝

so when one of these newly charged bodies comes into contact with another material,

所以當其中一個新的帶電物體 接觸到另一個材料時

the mobile electrons will take the first chance they get

可移動的電子一有機會就會

to go where they're most needed,

移到最需要它們的地方

either jumping off the negatively charged object,

不論是跳離帶負電的物體

or jumping onto the positively charged one

或是跳到帶正電的物體上

in an attempt to restore the neutral charge equilibrium.

都是要試圖回復到中性的電荷平衝

And this quick movement of electrons, called static discharge,

這種快速的電子移動 稱為靜電釋放

is what we recognize as that sudden spark.

就是我們認知中突然出現的火花

This process doesn't happen with just any objects.

這個過程並不會發生在所有物體上

Otherwise you'd be getting zapped all the time.

不然你就會隨時被電到

Conductors like metals and salt water

像金屬與鹽水之類的導體

tend to have loosely bound outer electrons,

傾向帶有鬆散的外層束縛電子

which can easily flow between molecules.

這些電子很容易在分子間流動

On the other hand, insulators like plastics, rubber and glass

相反的，像是塑膠、橡膠 與玻璃之類的絕緣體

have tightly bound electrons that won't readily jump to other atoms.

它們有緊密的束縛電子 無法輕易跳到別的原子上

Static build-up is most likely to occur

靜電累積幾乎都發生在

when one of the materials involved is an insulator.

其中一種材料是絕緣體的時候

When you walk across a rug,

當你踩過地毯時

electrons from your body will rub off onto it,

電子會從你的身體磨擦 掉到地毯上

while the rug's insulating wool will resist losing its own electrons.

然而地毯的絕緣毛線 會抵抗失去它原有的電子

Although your body and the rug together are still electrically neutral,

雖然你的身體和地毯加在一起 仍然算是不帶電

there is now a charge polarization between the two.

不過在這兩者間進行了電荷極化

And when you reach to touch the door knob,

所以當你去接觸門把時

zap!

觸電了！

The metal door knob's loosely bound electrons hop to your hand

金屬門把的鬆散束縛電子 會跳到你的手上

to replace the electrons your body has lost.

來取代你身體已經失去的電子

When it happens in your bedroom, it's a minor nuisance.

當這發生在臥室時 只能算是小麻煩而已

But in the great outdoors,

如果是在空曠的戶外

static electricity can be a terrifying, destructive force of nature.

靜電可以是自然界中 可怕且具毀滅性的力量

In certain conditions, charge separation will occur in clouds.

在某種情況下 電荷分離會發生在雲層中

We don't know exactly how this happens.

我們不知道到底是如何發生的

It may have to do with the circulation of water droplets

有可能與小水滴

and ice particles within them.

以及其中的冰粒循環有關

Regardless, the charge imbalance is neutralized

不論如何，中和電荷不平衡

by being released towards another body,

要靠朝向另一物體釋放電荷

such as a building,

例如朝向建築物

the Earth,

地面

or another cloud in a giant spark that we know as lightning.

或巨大火花──即閃電── 之中的另一朵雲

And just as your fingers can be zapped over and over in the same spot,

就像你的手指頭會 常常被同一個地方電到

you better believe that lightning can strike the same place more than once.

你最好相信閃電也可以 再次擊中相同地點