The path that leaping electrons follows depends on the material they flow through.
电子跳跃的路径取决于它们流经的物质。
The human body certainly will conduct current but not a lot, not like a piece of copper.
人体当然会传导电流,但不会很多,不像一块铜。
Copper has a lot of loosely held electrons, so it's a good conductor.
铜有很多松散排列的电子,所以它是一种很好的导体。
The electrons of clay and rubber are too tightly bound to their atoms to conduct electricity.
粘土和橡胶的电子与它们的原子结合得太紧密,无法导电。
They're said to be insulators.
它们被称为绝缘体。
How electrons begin to move in the first place is a result of a force of nature called electromagnetism.
电子如何开始运动是一种被称为电磁力的自然力的结果。
Our whole technological civilization exists because electricity can make magnetism.
我们整个科技文明的存在是因为电能产生磁性。
And, magnetism can make electricity.
而且,磁性能发电。
It goes back to the fact that we have two kinds of forces that are present that we call electricity or electromagnetism, and those two forces are the electric force and the magnetic force.
它可以追溯到这样一个事实:我们有两种力,将其分别称为电或电磁,这两种力就是电力和磁力。
![认识电力(3).jpg 认识电力(3).jpg](http://upload.kekenet.com/2020/1202/78961606895148.jpg)
The fundamental charges are a positive charge and a negative charge.
基本电荷是正电荷和负电荷。
To see these forces at work, head north and look up into the night sky.
要想看到这些力量在起作用,你可以向北看夜空。
Basically, the northern lights are the result of high energy electrical currents from the sun that are caught and guided by the Earth's magnetic field.
基本上,北极光是来自太阳的高能量电流被地球磁场捕获和引导的结果。
There's electricity out there.
那里有电。
Five, four, three, two, one.
五,四,三,二,一。
And, we have lift-off of the Space Shuttle Columbia continuing space research through the satellite of modern technology.
而且,我们已经发射了哥伦比亚号航天飞机,通过现代技术卫星继续进行太空研究。
On February 25th, 1996, NASA and Italian researchers made a bold attempt to harness the power in the atmosphere.
1996年2月25日,美国宇航局和意大利的研究人员大胆尝试利用大气中的能量。
They generated electricity with a satellite and a wire.
他们用卫星和电线发电。
It worked. Let's make sure we stay that way. Understand.
成功了。我们一定要保持这样。明白。
The mission was part of a new experiment of tethering satellites in space.
这次任务是一项新的太空系留卫星实验的一部分。
The experiment was based on the simple principle that when you move a conductor through a magnetic field electrons start to flow.
这个实验基于一个简单的原理:当你移动导体穿过磁场时,电子开始流动。
This generates an electrical current that can flow through a circuit.
这就产生了一个可以流过电路的电流。
The satellite was thrust into space using small gas jets and a thirteen mile long cable began to unreel.
这颗卫星是用小型气体喷射器送入太空的,一根13英里长的电缆开始展开。
And, if you put a, a wire inside of that tether you now have a moving wire that moves across a magnetic field.
如果你把一根电线放在绳子里,你现在有一根移动的电线,在磁场中移动。
That magnetic field, in this case, is the Earth's magnetic field, and the motion is the motion of the Space Shuttle moving at very fast, high velocities, orbital speeds.
这个磁场具体来说就是地球的磁场,它的运动就是航天飞机的运动,非常快的轨道速度。