时差N小时 富兰克林与电荷试验(下)（在线收听）

That’s why he was hanging them by strings; when they are free to move, you can easily see the attraction and repulsion at work.

这就是他用细绳将它们悬挂起来的用意。当它们可以自由运动时，很容易就会发现它们相吸和相斥的场面。

Nowadays we know that what Franklin was doing was finding different ways to change the net electrical charge on various substances by knocking around electrons.

如今，我们了解到富兰克林实验目的是寻求各种不同的方法，通过撞击电子改变电子对不同物质的净电荷。

Electrons are tiny, negatively charged particles.

电子是微小的带负电荷的粒子。

Since objects start out with equal amounts positive and negative charge, rubbing electrons off a glass rod with silk will give the glass net positive charge.

由于媒介起初带有相同数量的正负电子，玻璃棒与丝巾摩擦导致玻璃棒只带有净正电子。

Franklin didn’t know about electrons, but using only very simple materials, he had shown that opposite charges attract and like charges repel! He even coined the terms “positive” and “negative.”

富兰克林并不知道电子，但他利用极为简单的材料证明了异性电荷相互吸引，同性电荷相互排斥！甚至创造出了专有名词“正”和“负”。

Not bad for someone who was helping found new countries in his spare time.

对于一些人来说，建立一个新国家时，有点业余爱好，做点新鲜事也是个不错的选择。