-
The formula tells us or absorbed based on the energy difference between the two levels that we're going between, that the electron is transitioning between.
这些公式告诉我们,或发出的光的，频率大小,是基于，电子转移的，两个能级，之间的能量差。
-
He drinks all of my milk.
他把我们的牛奶喝光了。
-
Here's Samson: O first created Beam, and thou great Word, ; "Let there be light, and light was over all"; Why am I thus bereav'd thy prime decree?
参孙说到：,为什么我被剥夺你这第一道命令，“我们要有光！“光就普照一切;,为什么我被剥夺你这第一道命令？
-
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。
-
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。
-
Let's not just look at the United States; let's look at every country of the world and let's see if they have an equity premium.
不要光看美国,我们观察下世界上所有的国家,看看他们是否也存在股权溢价现象
-
Suppose we had X-ray vision and could see through the building.
假设我们有X光,可以看穿仓库。
-
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。
-
And one thing that Einstein put forth is he figured if well, what we're saying is that light is, in fact, a stream of particles, each one of those particles or photons must, therefore, have a momentum.
爱因斯坦提出了一件事情,他指出如果我们所说的光，事实上是一束粒子，那么这些粒子或者光子中的，每一个都有动量。
-
And sometimes we model light as a wave.
有时候我们把光看成一种波。
-
And instead of having the electron giving off energy as a photon, instead now the electron is going to take in energy from light and move up to that higher level.
与电子以光子形式施放能量不同,我们现在要从光中,获得能量到一个更高的能级。
-
We can only imagine the fallen angels with a kind of dim uncertainty just as the belated peasant sees, or perhaps he only dreams he sees, the dance of fairy elves by a forest side.
我们只能想象出堕落的天使们带着暗淡的变幻的光,正如他见到的，又或者是他梦见的，林边跳舞的精灵们。
-
What we had just done a clicker question on is discussing light as a particle and the photoelectric effect, so we're going to finish up with a few points about the photoelectric effect today.
我们刚才做得课堂表决器那个问题,是讨论光作为一个粒子以及光电效应，所以今天我们将以一些,关于光电效应的观点作为结束。
-
I'm sure there's some upper limit as there are to most things, like if we think of wavelengths and different types of light, there is so large that you can get, but you would be approaching that level.
我确信对于大多数事物,都会有一个上限，就像我们考虑波长和不同的光时，那个太大了，但是你可以接近那个量级。
-
And sometimes it's a matter of factors that you need to figure out what it is, and maybe it's that there's extra light in the room we don't know about.
而且有时候它是,需要计算的一个因素，有时候这个房间里可能有,我们未知的额外的光。
-
So, for example, we were talking about a threshold frequency as in a minimum frequency of light that you need in order to eject an electron from a metal surface.
举个例子来说，我们谈论的临界频率是,光从金属表面逐出一个电子,所需的最小频率。
-
And we'll also talk about photon momentum as another example of light behaving up as a particle.
并且我们也会讨论光子动量的问题,这个可以作为光有粒子行为的例子。
-
We're in between absolute day and absolute night, light and dark.
我们处在绝对的日与绝对的夜之间，光与暗。
-
Absorption is just the opposite of emission, so instead of starting at a high energy level and dropping down, when we absorb light we start low and we absorb energy to bring ourselves up to an n final that's higher.
吸收就是发射的逆过程,与从一个高能量到低能量不同，当吸收光时，我们从低能量开始,吸收能量到一个更高的能量。
-
And this is a very fast speed, of course, it's about 700 million miles per hour. So, one way to put that in perspective is to think about how long it takes for a light beam to get from earth to the moon. Does anyone have any guesses? Eight seconds, that sounds good.
当然这是一个非常快的速度，它大约是每小时7亿英里,为了更形象化，我们,看看光从地球到月球,需要多少时间，你们猜猜是多少？,8秒，猜的不错。
-
And what you see when we see it with our eye, which is all the wavelengths, of course, mixed together, is whichever those wavelengths is most intense. So, when we looked at the individual neon lines, it was the orange colors that was most intense, which is why we were seeing kind of a general orange glow with the neon, which is different from what we see with the hydrogen.
当你们用眼睛看时，当然看到的是全波长，是混在一起来，看到的是最强的那些波长，当我们看单个氖谱线时，橙色是最强的,所以我们看氖光整体是橙色的,这和氢气是不一样的。
-
So this is our final equation, and this is actually called the Balmer series, which was named after Balmer, and this tells us the frequency of any of the lights where we start with an electron in some higher energy level and we drop down to an n final that's equal to 2.
把2代入到这里，所以得到1除以,这就是我们最终的方程，这叫做Balmer系，以Balmer名字命名的,它告诉我们从高能级掉到n等于2的,最终能级所发出光的频率。
-
But we don't have X-ray vision.
但我们没有X光。
-
Shiller and Siegel are next to each other in the alphabet, so I was standing in line with him for an x-ray and I got to talking with him and I've known him ever since.
希勒和西格尔按字母顺序是相邻的,所以我和他站在一起排队照X光,我们开始聊天,从此我就认识他了
-
So, we'll take a little bit of a step back after we introduce quantum mechanics, and talk about light as a wave, and the characteristic of waves, and then light as a particle. And one example of this is in the photoelectric effect.
等我们介绍完量子力学后,我们要回过头来讨论下光,作为一种波和它的波动性特征,以及光作为一种粒子,其中的一个粒子就是光电效应。
-
That makes sense because we're losing energy, we're going to a level lower level, so we can give off that extra in the form of light. And we can actually write the equation for what we would expect the energy for the light to be.
这很合理，因为我们在损失能量,我们要到一个更低的能级去,我们要以光的形式给出额外的能量,我们可以写下光能量的方程。
-
For example, if we talk about photons, of course, we also just mean light, sometimes we refer to this as electromagnetic radiation, and there's several ways that you might be asked this in a problem or that you might be asked to answer.
举例来说，如果我们讨论光子，当然我们也叫做光，有时候我们看作是电磁辐射，而且这里有几种方式,你可能会在题目中被问到,或者被提问回答。
-
So it turns out that we can, in fact, use the energy levels to predict, and we could if we wanted to do them for all of the different wavelengths of light that we observed, and also all the different wavelengths of light that can be detected, even if we can't observe them.
事实上我们可以用能级预测,而且如果我们想的话，我们可以,对所有观测到的光的波长预测，也可以对所有探测到的光预测,即使我们看不到它们。
-
So that's the important take-away message from this slide. If we think about these different types of lights, microwave light, if it's absorbed by a molecule, is a sufficient amount of frequency and energy to get those molecules to rotate. That, of course, generates heat, so that's how your microwaves work.
重要的信息，如果我们看看,这些不同种类的光，微波,如果被分子吸收，它的频率和能量可以,使分子转动,这当然的，会产生热量,这就是你们微波炉的工作原理。
-
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。
应用推荐