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OK, so we've got UV light here, and let's see what we can see, and we lose electrons, if that's what's happening.
好了，我们已经有了紫外光源，让我们来看看能观察到什么，如果那些事情发生了，我们将会失去电子。
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We know that UV light gets absorbed by glass, so it shouldn't be able to go through the glass.
我们知道紫外光会被玻璃吸收，所以它无法通过玻璃。
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If you get some of these in the upper atmosphere, a photon, an ultraviolet photon, has the energy capable of breaking this bond.
如果你把它放到大气层上，一个光子，一个紫外光光子，有能量可以破坏它的化学键。
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So, ideally what we did see was, in fact, it does have enough energy with the UV lamp, it wasn't a dramatic shift you saw because we didn't start very high and then it went to that stuck point.
所以，理想上我们所看到的，事实上，紫外灯没有足够的能力，因为我们没有从非常高开始,所以它没有一个特别显著的移动,然后它又回到了黏着点。
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So that means we're going to need to figure out what is the energy per photon that's emitted by that UV light.
所以那意味着我们将需要,计算出从紫外光源发射出的,每个光子的能量。
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I wonder if there's some UV light out of this new lighting set up in our classroom here.
好的，我想知道这里,我们教室里的这套新的照明装置,是否有一些紫外光出来。
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We have a UV lamp right here, which is centered at a wavelength of 254 nanometers.
我们有一个紫外灯在这里，波长集中在254纳米处。
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It'll still likely get stuck in that spot, but we'll just show you one more time the effects of the UV light, and actually we'll throw in an extra trick here, too.
它仍然像是在那点卡住了，但是我们还是会再展示一次,紫外光源的效应，事实上，我们也会引入一个新的技巧。
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So, we would expect to see electrons ejected with the UV light source.
所以，我们能够预测,可以看到电子被紫外光源射出。
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So if we think about the work function for zinc, and the work function for zinc is 6.9 times 10 to the -19 joules, do we expect that when we shine our UV light on the zinc, we'll be able to eject electrons?
如果我们考虑锌的功函数,它是6，9乘以10的-19次方焦耳，我们是否可以预测当,用紫外灯照射锌时，我们可以射出电子呢？
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So, if you use a black lamp or something and you excite something up to a higher energy level and then it relaxes back down to its lower energy state, it's going to emit a new wavelength of light, which is going to be visible to you.
如果你用一个紫外灯或别的,东西把某种分子激发到,更高的能级，然后它会掉回,到低能级，它就会释放,一个新的波长的光,这个光是可见的。
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Yeah. It was UV light that we used.
对，我们用的是紫外光。
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So we can figure out the energy of each photon emitted by our UV lamp by saying e is equal to h c over wavelength.
所以我们可以计算出,每个从紫外光源射出的光子,也就是e等于h乘以c除以波长。
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And I also want to point out, it's guaranteed pretty much you may or may not be able to see, sometimes it's hard to see that one that's getting near the UV end of our visible spectrum. So we won't worry if we can't see that.
我要指出的是，我可以保证你们,但你们可能会看不到，有时候很难看到,这个可见光谱边缘接近紫外光地方的这根谱线,所以看不到也不用担心。
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We can think about the Lyman series, which is 1 where n equals 1. We know that that's going to be a higher energy difference, so that means that we're going to be in the UV range.
我们可以来看看Lyman系,也就是n等于,我们知道它的能量差更大,所以它在紫外光区内。
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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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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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