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认识电力(1)

Everyone has to obey the laws of physics, even if you're the King. The power to make night into day, create life or cause death, this is all part of the mystery and magic of electricity.

Long before we knew what it was . . . long before we harnessed it . . . electricity was flowing through our bodies descended from the heavens. So, there's constantly current flowing into the Earth from thunderstorms and flowing out where there's not thunderstorms and in that process an electric field is generated in the atmosphere.

We walk around, the voltage between your head and your toes when you walk around is two or three hundred volts, and nobody notices that because you grew up in it. But, when there is enough of a voltage difference between the clouds and the Earth, it's hard not to notice.

One of those who was fascinated by the phenomenon was Benjamin Franklin. Ben Franklin was a really smart guy.

He, he was one of the original experimenters with electricity, period. He, in fact, invented the designation of positive and negative charge.

Today, high technology has replaced the kite. In North Central Florida scientists summon lightning and bring it to the Earth with a rocket and a wire.

We can make the cloud produce lightning and direct it where we want to direct it to do tests, and that really hasn't been possible before. They direct the lightning to strike simulated houses and power lines to understand what happens when it hits.

The rocket launch provides a more controlled experiment than anything Ben Franklin could have imagined.

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