Name: 如何在雷擊中生存 (How to Survive a Lightning Strike)
Uploaded: 2021-01-14T05:08:44.000Z
Duration: 2 min 33 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

If you get caught in the middle of a big, open field during a lightning storm, which

of the following uniforms would be most likely to keep you safe? A thick wetsuit; a superman

costume; a medieval coat of armor; or a birthday suit?

If you answered "medieval coat of armor," you might be a little crazy--but you'd also

be right. You'd be crazy, of course, because lightning is much more likely to strike metal

than to strike rubber, fabric, or bare skin. The reason is that lightning bolts are just

long streams of fast-flowing electrons looking for the easiest path from point A to point

B, and no everyday material provides an easier path than metal.

So why would a material that lures lightning bolts keep you safe during a thunderstorm?

Ironically, for the exact same reason it attracts the the lightning in the first place: metal

is a great conductor of electricity. Electrons glide so easily over metals that they barely

penetrate into the surface. And if an electrical current happens to be moving over a hollow

metal container, like a can or a box or even a welded coat of armor, the current won't

Physicists call this kind of container a Faraday cage . Or, in the case of the steel-woven

clothing worn by linemen working on high-voltage wires, a Faraday suit.  In fact, your car

is an everyday example of a Faraday cage, which is why--despite what you may have heard

about rubber tires--it's actually the closed metal body surrounding you that keeps you

safe. It channels lightning around, rather than through you.

Of course, if you're away from your car and get caught in an open field during a storm,

chances are slim that you'll have a medieval coat of armor or high voltage line-suit handy.

In that case, whether you're naked or in costume, your body unfortunately happens to be a better

electrical conductor than both air and soil, so it provides a great shortcut for traveling

current. Stand upright, and you're the fastest route for a descending lightning bolt. Lie

down, and you're the best path for current racing along the ground from a nearby strike.

So the best thing to do is crouch low and keep your feet close together. Crouching low

is obvious. But similarly important, when your feet are right next to each other, your

legs don't make for much of a shortcut for the current to get from A to B. And even if

they are the best path for the lightning, when your feet are the only thing touching

the ground, then the current will most likely travel up one leg and down the other, missing

critical organs like your heart--something these cows couldn't avoid.

But, actually, the real best thing to do is avoid lightning altogether--armor or no armor--and

head indoors when you spot a storm on the horizon.