Our ionization energy is going to be equal to the incident energy coming in, minus the kinetic energy of the electron.
我们的电离能将等于,入射能量,减去电子的动能。
In this case, it's called the ionization energy, plus whatever kinetic energy we have left over in the electron.
在这种情况下,它就是电离能,剩余部分将转化为,出射电子的动能。
If you took a 15 inch artillery shell moving at the velocity it typically goes at, and take that amount of kinetic energy versus the resistive capacity of a sheet of tissue paper, that's the scale that we're looking at here.
如果你有1个15英寸的炮弹,按照经典的速度移动,会消耗大量的动能,抵抗来自于一张薄纸的阻力,这就是我们在这儿看到的尺度。
So, for example, in the second case, we say that we see 12 06 in terms of the kinetic energy.
比如,在第二种情况下,我们观测到,1206大小的动能。
The second piece of information we need to know is what actually the kinetic energy is of the ejected electron, and that's something we can just measure by measuring its velocity.
其次,我们需要知道的信息是,出射电子的动能,这可以通过,测量它们的速度得到。
So in the case of 12 32, that is our highest kinetic energy, it's the smallest amount of energy it takes to pop an electron out of that orbital.
因此,1232是我们能够得到的,最高的动能,它是从这个轨道中,打出一个电子需要消耗的最低能量。
And what we have left over is this amount of energy here, which is going to be the kinetic energy of the ejected electron.
都用来发射它,剩下的这些就是,出射电子的动能。
It means that we better get away from these deterministic models where we have a little electron here with its potential energy and its kinetic energy.
它的意思是我们最好远离,这些确定性模型,那里有一个小电子,它具有势能和动能。
And let's look at the final kinetic energy that we'd observe in this spectrum, which is 384 electron volts, so what is that third corresponding ionization energy?
然后让我们来看一下,在光谱中观测到的,最后一种动能,它大小是,384,电子伏,那么这相应的第三种电离能是多大?
And what we would see if we were graphing, for example, increasing kinetic energy, is we would see 1 line corresponding to each of these energies of electrons that we see coming out.
如果我们将它画出来会看到,比如以动能增加的顺序,这里一条线就对应着,一个出射电子可能带有的动能中的一种。
So, what we would expect is that there is a relationship between intensity in kinetic energy because it was understood that however intense the light was, if you had a more intense light, it was a higher energy light beam.
光强和能量之间,应该有一定的关系,因为在我们的理解中,不管光强是多少,光的强度越大,光束能量越高。
The next thing that they wanted to look at was the actual intensity of the light and see what the relationship of intensity to kinetic energy is.
下一而他们要研究的是光的强度,看一下光强和能量之间的,关系是怎样的,我们预期。
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。
So, you can imagine, that we'll actually probably have a lot of kinetic energy left over if we put a lot of energy in in the first place.
因此,可以想象,如果我们一开始,就注入大量的能量,那么得到的动能也应该很大。
And it turns out that the first kinetic energy that we would see or the highest kinetic energy, would be 12 32 electron volts.
结果是我们最先观测到的动能,也就是最大的动能,将是,1232,电子伏,那。
So another way to think about that is just the rotational kinetic energy of our electron.
或者,这样想,它是,电子旋转的动能。
And this is what they had expected that there would be no relationship, but instead here they saw that there was a linear relationship not to the intensity and the kinetic energy of the electrons, but to the intensity and the number of electrons.
另外一个实验,他们预期这两者没有关系,但他们看到的不是,光强和电子动能的,线性关系,而是光强,和电子数的线性关系。
We can also talk about it in terms of if we want to solve, if we, for example, we want to find out what that initial energy was, we can just rearrange our equation, or we can look at this here where the initial energy is equal to kinetic energy plus the work function.
初始能量是多少,也可以,写成另一种形式,我们可以把方程变形,或者我们看这里,初始能量等于,动能加功函数。
So, one thing they did, because it was so easy to measure kinetic energy of electrons, is plot the frequency of the light against the kinetic energy of the electron that's coming off here. And in your notes and on these slides here, just for your reference, I'm just pointing out what's going to be predicted from classical physics.
他们做的其中一件事,因为测量电子动能是很容易的,就是画出光的频率,和出射电子动能之间的关系,在讲义的这里,仅仅是,为了做个比较,我要指出,经典物理所给出的预测,这个不作为对你们的要求。
So that should mean that the energy that's transferred to the electron should be greater, but that's not what you saw at all, and what you saw is that if you kept the frequency constant there was absolutely no change in the kinetic energy of the electrons, no matter how high up you had the intensity of the light go.
所以这意味着转移到电子,上的能量也越大,但这并不是,我们观测到的现象,我们所看到的是,如果固定光的频率不变,不管光强如何变化,电子的动能没有任何变化。
And we know that n describes the total energy, that total binding energy of the electron, so the total energy is going to be equal to potential energy plus kinetic energy.
我们知道,n是描述总能量的,电子总的结合能,所以总能量,等于,势能加动能。
And if that is the energy to go from n equals one n=2 this is the amount of energy that has to be left as kinetic energy of the electron.
如果这个能量是从n=1到,然后,to,n,equals,two,then,这些能量,会作为电子的动能,被消耗掉。
So instead you'd have to maybe if you start with wavelength, go over there, and then figure out velocity and do something more like kinetic energy equals 1/2 n b squared to get there.
这时你要先从波长开始,到这,然后算出速度,然后像动能等于1/2nb平方得到这。
So if we say that l is just talking about our kinetic energy part, our rotational kinetic energy, and we know that electrons have potential energy, then it makes sense that l, in fact, can never go higher than n.
如果我们说,l仅仅是,描述动能项,我们的旋转动能,我们知道,电子有势能,所以可以理解,l不能比n高。
So that's why we see the 2 p here, 1206 the 2 s is 12 06, and it makes sense that what we see as the greatest ionization energy, which is also the smallest kinetic energy is that 1 s orbital.
这就是为什么我们看到,2,p在这里,2,s对应,那么我们看到对应最高的电离能,同时也对应最低的动能的,应该就是,1,s,轨道。
The total energy of the system, which we are going to get from postulate number four, which says the energy of the electron, which is the energy of the system, is the sum of the kinetic and the potential energy.
这个系统的总能量,也就是我们将从第四个假设中算出的能量,也就是电子运动产生的能量,也就是整个系统的能量,是动能和位能的总和。
So, that was frequency with kinetic energy.
这是频率和动能。
We can do the same thing for the other observed kinetic energy.
我们还可以对观测到的,其它动能进行同样的操作。
So, therefore, we can rewrite our equation in two ways. One is just talking about it in terms only of energy where our kinetic energy here is going to be equal to the total energy going in -- the energy initial minus this energy of the work function here.
所以我们可以把方程,写成两种形式,一个是,只考虑能量,动能等于总的,入射能量-初始能量减去,功函数的能量,我们如果想解决,比方说,我们想知道。
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