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Let's look at the energetics of one of those electrons crashing into a hydrogen atom inside the gas tube.
我们一起来考察一下,其中的一个电子的能量,在阴极射线管中,撞击到氢原子上。
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So, we know now that we have charged particles. Are these negatively or positively charged based on this evidence?
弯曲的角度,现在我们知道,阴极射线是带电粒子,但从这个实验？
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So rather than calling this an electron beam, this was called a cathode ray.
因此我们最好别叫它电子束，而是阴极射线。
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How do I posit-- why do I believe in x-rays, even though I don't see them?
我如何证实,我为什么会相信X射线是存在的,尽管我压根看不见它
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It allows us to look not just at the anatomy of what's going on inside your body like an x-ray does, but to look at the chemistry, the biochemistry of what's happening inside a particular organ or tissue in your body.
这种方法不仅能够像X射线那样,使我们从解剖学的角度观察体内的情况,还能了解到,在体内特定的组织和器官中,发生的化学 确切说是生物化学过程
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So, when the voltage difference between the plates is zero, or when we just don't have the plates there at all, the cathode rays are not bent, they just go right in a straight line, and they can be detected on this screen.
拐弯来测试它们是否带电,当两板之间电压为零，或者根本就,没有这两个板时，阴极射线是一条直线,它可以在屏幕上。
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Sometimes we model light as beams of light, as rays of light.
有时候我们把光看成光束模型，看成光射线。
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And so, we've got a beam.
这样我们就能得到一束射线。
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PROFESSOR: Yeah, that's right. So, what we have here, cathode rays we now know are negatively charged particles. And, in fact, he named these negatively charged particles. Does anyone know what he named them? No, not electrons - very good guess. He named them corpuscles.
学生：负电，教授：是的,我们现在知道，阴极射线是带负电的粒子,实际上他还给这些,带负电的粒子去了一个名字,有谁知道叫什么吗？
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The second particle was deflected almost not at all. But what he could tell from the fact that there was a second particle at all, and the fact that it was in this direction, is that in addition to his negative particle, he also, of course, had a positive particle that was within this stream of rays that were coming out.
粒子的强烈信号,有着强烈的对比,第二个粒子几乎，不发生偏转，他能判断这是，第二个粒子的原因是它在这个方向,所以在出射射线中,除了有带负电的粒子外。
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So the way that we really make sure this is done is that we use x-rays.
我们保证能做到这一点的方法是,使用，X，射线。
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People have been working with x-rays for about 30 years by this time.
到现在为止,人类和X射线打交道大约30年了。
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This is the equivalent to ray optics, isn't it?
这与X射线是等价的，是不是？
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They took a crystal, this is a single crystal of nickel that has regular planes of atoms, and those planes are spaced on the order of an angstrom or less apart, and they irradiated this with x-rays.
他们取了个晶体,一个具有规则原子平面的，镍晶体,这些面间距差不多也是一埃或者更少，它们放射出X射线。
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And if I evacuate it, I have a cathode ray tube.
如果我对其抽真空，我会得到一根阴极射线管。
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On the other hand, when it came to penetrating solids, penetrating solids, the alpha radiation was poor at penetrating solids, whereas the beta radiation was very good at penetrating solids.
另一方面，当研究穿过固体的时候，嗯，穿过固体，会发现阿尔法射线很难穿过固体，然而贝塔射线,很容易穿过固体。
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Well, we can't guarantee with UV light we'll have enough energy to eject every single electron, so that's why when we use x-rays, they're higher energy, you can pretty much be guaranteed we're going to eject all of those electrons there.
好，我们不能保证紫外光有足够的能量,激发出每一个电子，所以我们要使用，X，射线，它的能量更高，你可以非常确定,我们可以激发出其中所有的电子。
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And what we did was he put two detection plates on either side of these cathode rays, and when he put a voltage difference between these two plates, he wanted to see if he could actually bend the rays and test if they're actually charged or not.
但没有实验证明这件事,这就是Thomson所做的，它在阴极射线旁边放两块探测板,他想通过看当他,在两板之间加上电压后,阴极射线是不是会。
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Here it is showing x-rays. He used x-rays.
这展示的是X射线，他使用X射线。
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So you know that x-rays are higher frequency than UV light, for example, that means it's also higher energy than UV light, and if you think back to our photoelectric effect experiments, do you remember what type of light we were usually using for those? Does anyone remember?
你们知道，X，射线的频率比紫外光高，这意味着，它的能量也比紫外光要高，那么，请大家回想一下我们的光电效应实验，大家还记得当时我们用的是什么光源吗？,有人记得吗？
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