No, OK and that's correct, because each photon of light actually has more energy than is needed to eject an electron.

没有，好，对了，因为每一个光子实际上,都有更多的能量去逐出一个电子。

麻省理工公开课 - 化学原理课程节选

Yes. In fact, there is not enough energy in a single photon to go ahead and eject an electron from this zinc surface.

是的，事实上，这里的光子没有足够的能量,去从锌表面逐出一个电子。

麻省理工公开课 - 化学原理课程节选

So what we're saying here is the incident energy, so the energy coming in, is just equal to the minimum energy that's required to eject an electron.

这里我们来讨论一下，入射能量正好等于,发射出一个电子所需要的最低能量的情况。

麻省理工公开课 - 化学原理课程节选

If we have a higher z effective, it's pulled in tighter, we have to put in more energy in order to eject an electron, so it turns out that that's why case 2 is actually the lowest energy that we need to put in.

而如果有效核电量更高，原子核的束缚也就更紧，我们不得不输入更多的能量来打出一个电子，这就是第二种情况,所需要输入的,能量更少的原因。

麻省理工公开课 - 化学原理课程节选

We're only using up a little bit to eject the electron, then we'll have a lot left over.

如果我们只需要用很少一部分来发射出电子，那么我们可以得到很多的剩余能量。

麻省理工公开课 - 化学原理课程节选

So we can use an equation to relate the incident energy and the kinetic energy to the ionization energy, or the energy that's required to eject an electron.

因此我们可以用一个公式将入射能量,与动能和电离能，就是发射出一个电子所需要的能量关联起来。

麻省理工公开课 - 化学原理课程节选

So we see that we do not eject electrons in the case of the laser pointer, even if we have this intensity, it is still not related to the energy of an individual photon, so we won't see an effect.

所以我们看到我们用激光笔,还是没有逐出电子，即使我们有这样的强度，它仍然与一个单个的光子能量无关,所以我们不会看到光电效应。

麻省理工公开课 - 化学原理课程节选

putting all those things together, if you looked at this question again we'd get 100% on it, 0 9 that our only option here is 0. 9, and that it's not the negative, it's the positive version, because we're talking about how much energy we have to put into the system in order to eject an electron.

把这些放在一起，你们再看一下题目,大家100%都能选对，我们唯一的选择就是这个，它不是负数，它是正的，因为我们说的，是要,把电子激发出来,需要提供的能量。

麻省理工公开课 - 化学原理课程节选