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Alexander said the Obama administration's proposed subsidies for solar, wind and agricultural energy development will not make much difference, since those forms of energy provide less than two percent of America's electricity.
VOA: standard.2009.04.25
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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。
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So, similarly in a case where instead we have a small energy difference, we're going to have a low frequency, which means that we're going to have a long wavelength here.
在这个例子里,能量差较小,我们得到的频率低,这意味这它的波长更长。
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And the answer lies clearly in the energy difference.
从能级差看，答案很明显。
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And then the investigators actually measured these things, and found that with reported and actual energy intake, how many calories people were consuming, there was really quite a difference.
研究人员实际上得到了以下结果,实验对象汇报的和实际的能量摄入,也就是人们摄入的卡路里,两者有较大差异
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So that should make sense, because we saw no energy difference between the actual atoms and the molecules.
这很好理解，因为我们看到,原子和分子的能量差为零。
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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。
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And you have to ask yourself is the energy difference here, the delta E in the electronic states, how does that compare with the E of visible light?
所以我们会问,是由于能量的不同么，例如deltaE在电子能态的不同，那如何把E与可见光联系起来？
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PROFESSOR: Good. So, it's going to be in 3, because that's the shortest energy difference we can have, 3 those 2 are inversely related, so it must be n equals 3.
教授：好，是3，因为它的能量差最小，红色的是我们能看到的，所以一定是n等于。
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So, this raises kind of an interesting question in terms of what the difference is between these two cases, and we're talking about numbers of energy.
那么，到这里就出现了一个很有意思的问题,那就是下面这两种情况的区别在哪里？,当然我们关心的是能量的多少。
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What people did is they said let's define a unit of energy that represents a unit charge accelerated across a unit potential difference, and let's call that the electron volt.
前人们所做的就是他们说让我们确定,一个能量单位用来代表一单位电荷,加速穿过形成的一单位电势差，我们叫它电子伏特。
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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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One major difference between electron affinity and ionization energy is that when we talked about ionization energy, remember ionization energy always has to be positive.
电子亲和能,与电离能之间最大的不同就在于,当我们提到电离能的时候，记得电离能总是正的。
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So, if we want to go from that stable state to that less stable state, we need to put in a certain amount of energy to our system, that difference between the free electron and the electron bound to the metal.
所以，如果我们想使电子,从稳态到达不够稳定的状态，我们需要引入一定数量的,能量到系统中，即自由电子和束缚于金属的,电子的能量差。
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So that's just a little bit of a check for yourself, and it should make sense because what you're doing is you're calculating the difference between energy levels, so you just need to flip around which you put first to end up with a positive number here, and that's a little bit of a check that you can do what yourself.
所以你们总要确保括号，离得这项是正的，这是你们自己,可以做的检查，这事很有道理的，因为你们做的是计算能量差,所以你需要调整顺序来保证一个正数，这是你们自己可以做的检查。
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In the case of energy expenditure, how many calories people were burning, there wasn't quite such a difference, but again, it was in the favor of the individuals, that the people were estimating they burned this many calories from physical activity, but this is actually the number that they burned.
就能量消耗来说,人们消耗了多少卡路里,两者之间的差异并不是如此巨大,但又一次,由于人们的一厢情愿,人们估算从体育活动中,他们消耗了这么多的卡路里,但数据是他们实际消耗的
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So, that's the difference in thinking about different types of ionization energy, so it can get a little bit confusing with terminology if you're just looking at something quickly, so make sure you look really carefully about what we're discussing here.
所以，这就是我们,在思考不同类型的电离能时所看到的不同，因此如果你看得不够仔细的话,你可能会被其中的术语弄迷糊了，所以一定要看仔细,我们讨论的是什么。
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That is the difference between these two energy states.
这个能量就是两能级之间的能量差。
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it's an easy calculation -- we're just taking the negative of the binding energy, again that makes sense, because it's this difference in energy here. So what we get is that the binding energy, when it's negative, the ionization energy is 5 . 4 5 times 10 to the negative 19 joules.
这个计算很简单-我们,只需要取结合能的负值,同样这很容易理解，因为这就是这的能量差,所以我们得到的就是结合能,当它取负值，电离能就是5。45乘以。
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And the electrical energy is the product of the charge on the electron times the voltage which is the potential difference through which the electron was accelerated. And so this allows me to, by increasing the voltage, increase the energy on the electron.
电子能量是电子上的电荷数,乘以电压的结果,这是种内在的差距,通过它电子运动得以加速，这也让我，通过增强电压，来增加电子能量。
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So, if, for example, we were looking at a hydrogen atom in the case where we have the n equals 1 state, so the electron is in that ground state, the ionization energy, it makes sense, is going to be the difference between the ground state and the energy it takes to be a free electron.
电离氢原子所需要的能量,如果我们看n等于1的情况,电子在基态，那电离能，很合理的就是基态,和自由电子态的能量差。
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