-
When a light particle,or photon, hits an electron, the electron jumps to a higher energy state.
VOA: special.2010.09.01
-
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。
-
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。
-
If a photon which has no mass can behave as a particle, does it follow then an electron which has mass can behave as a wave? 1920.
如果一个没有质量的光子,能像粒子一样运动，那么它能像一个,没有质量的电子那样以波的形式运动吗。
-
That's sometimes confusing for people, because it seems like okay, is it a photon or is it an electron.
有时候这对人们来说是令人迷惑的，因为它看起来好像是对的，它是一个光子还是一个电子？
-
So for every photon we have 2.84 times 10 to the -19 joules.
每一个光子有,2，84乘以10的-19次方焦耳。
-
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。
-
Because here what we have is some atom that we're studying, in the case, it's going to be a gas, and we hit it with a photon that has some incident energy.
因为这里我们要研究的是一些原子,在这种情况下，一般是气态的，然后我们令一个,具有一定初始能量的光子打上去。
-
Well, if I go through that, the wavelength of such a photon is going to be so big that I am back to measuring the dimension of the human hair with the yardstick.
好的，如果我做完了这个，那个一光子的的波长将成为,我将回头测量的,用一个尺度测量出人头发的尺寸。
-
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。
-
And that will be associated with a wavelength if it releases the energy in terms of a photon.
是用光子的形式放出来的话,它会和光的波长相关。
-
If a photon, which has no mass, can behave as a particle --And we know this.
如果一个没有质量的光子，像粒子一样运动--，我们知道这个。
-
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。
-
Well, the energy of the photon, hv we know from Planck, is h nu, which is hc over lambda.
好吧，光子，我们从普朗克那得知，它是，即hc/lambda，波长。
-
So, remember what we're talking about here is the amount of energy that's in each photon.
所以，记住我们这里谈论的是,每个光子的能量值。
-
So, we do this here for the photoelectric effect, and in terms of the photoelectric effect, what we know the important point is that the incoming photon has to be equal or greater in energy then the work function of the metal.
所以，我们做这个是为了说明，光电效应，在光电效应方面，我们知道的最重要的事情,就是入射的光子能量必须等于,或者大于金属的功函数。
-
So it does not mean that we have more energy per photon.
它不代表每一个光子,有更高的能量。
-
And what we predict as an energy difference between two levels, we know should correspond to the energy of light that's either emitted, if we're giving off a photon, or that's absorbed if we're going to take on a photon and jump from a lower to a higher energy level.
我们预测，两个能级之间的能量差，我们知道，它要么和发出的光有关,如果它发出光子的话，要么它吸收光子,从低能级跃迁到，更高能级上去。
-
If I take lambda equals one angstrom, hc/lambda go through hc over lambda, you will discover that the energy of a photon with one angstrom as its wavelength is on the order of 12,400 electron volts.
如果我让波长等于一埃，能量为，你将发现光子的能量,当其波长为1埃的时候,相当于12，400电子伏特。
-
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。
-
The first that we need to know the energy of the photon that's incident on our gaseous atom.
首先，我们需要知道,入射到气体原子的光子的能量。
-
So this means that we can go directly from the energy between two levels to the frequency of the photon that's emitted when you go between those levels.
这意味着我们可以直接,从两个能级的能量得到它们之间,跃迁发射出光子的频率。
-
It's called this just because it's an electron that results when an electron absorbs a photon's worth of energy, so thus it's a photoelectron.
之所以这样称呼是因为,当一个电子吸收,一个光子的能量的结果，因此它是一个光电子。
-
Intensity, if we increase the intensity, we're not increasing the energy in each photon, we're just increasing the number of photons that we're shooting out of our laser, whatever our light source is.
强度，如果我们增加强度，我们增加的不是,每个光子的能量，我们增加的仅仅是,从我们激光源射出的光子数，无论我们的光源是什么。
-
We start at this lower energy state and go up that means we need to absorb a photon, we have to take in energy.
我们从一个低能级开始，到一个高能级去,这意味着需要吸收一个光子，我们要获得能量。
-
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。
-
And what is the energy of that photon?
那什么是光子呢？
-
And it is given off in the form of a photon.
它一个光能的形式释放。
-
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。
-
Photon emission, perhaps.
光子发射，可能。
应用推荐