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Then they use radio frequency energy to heat the tissue around the catheter.
VOA: special.2010.03.02
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So really what we'll probably do is instead either give you the wavelength or the frequency and you'll go ahead and calculate the energy from there.
所以实际上我们可能的做法是,给你波长或者频率,然后你可以通过他们计算得到能量。
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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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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。
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Any frequency can't have an energy, you have to -- you don't have a continuum of frequencies that are of a certain energy, it's actually punctuated into these packets that are called photons.
任何频率不能有个能量,你必须要-对某一个能量上,你不会有连续的频率,光子实际上分立的存在。
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So, the take-home message is whether you have three photons or 3,000,000 photons that you're shooting at your metal, if you're not at that minimum frequency or that minimum energy that you need, nothing is going to happen.
所以，这里表明的信息是,无论是向金属发射3个光子,还是300万个光子,如果没有达到所需的最低频率,或者最小能量,什么事情都不会发生。
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And what they could come up with, what they reasoned, is that there must be some intrinsic property within the electron, because we know that this describes the complete energy of the orbital should give us one single frequency.
他们想到着一定和，电子的本征性质有关，因为我们知道这个轨道的,完整描述会给出单一的频率。
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So, that was frequency with kinetic energy.
这是频率和动能。
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What Einstein then clarified for us was that we could also be talking about energies, and he described the relationship between frequency and energy that they're proportional, if you want to know the energy, you just multiply the frequency by Planck's constant.
爱因斯坦阐述的是我们,也可以从能量的角度来谈论，他描述频率和能量之间的关系,是成比例的，如果希望知道能量值，你用普朗克常数乘以频率就可以了。
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So, if we start instead with talking about the energy levels, we can relate these to frequency, because we already said that frequency is related to, or it's equal to the initial energy level here minus the final energy level there over Planck's constant to get us to frequency.
如果我们从讨论能级开始，我们可以联系到频率上,因为我们说过频率和能量相关,或者说等于初始能量,减去末态能量除以普朗克常数。
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And, as you know, Einstein made many, many, many very important contributions to science and relativity, but he called this his one single most important contribution to science the relationship between energy and frequency and the idea of photons.
于这些波包里，你们也知道，爱因斯坦在科学和相对论上,做出了非常非常非常多的贡献,但它把这个叫做他对科学,最重要的贡献，就是能量和,频率之间的关系以及光子的概念。
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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。
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So, for example, here we're showing rubidium and potassium and sodium plotted where we're plotting the frequency -- that's the frequency of that light that's coming into the metal versus the kinetic energy of the electron that's ejected from the surface of the metal.
让大家看来都是可以理解的事情,就是把不同金属的观测结果,画到一张图里面来，例如这里,我们展示的是钠，钾,铷的频率-这是照射金属的光的频率,和金属表面出射电子动能的关系。
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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。
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we start high and go low, we're dealing with emission where we have excess energy that the electron's giving off, and that energy is going to be equal the energy of the photon that is released and, of course, through our equations we know how to get from energy to frequency or to wavelength of the photon.
当我们从高到低时，我们说的,是发射,电子有多余的能量给出，这个能量等于，发出,光子的能量，当然我们可以通过方程,从能量知道，光子的频率，和波长。
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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。
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So, we can get from these energy differences to frequency h by frequency is equal to r sub h over Planck's constant 1 times 1 over n final squared minus 1 over n initial squared.
所以我们通过不同能量,得到不同频率，频率等于R下标,除以普朗克常数乘以1除以n末的平方减去。
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And I use the term photon here, and that's because he also concluded that light must be made up of these energy packets, and each packet has that h, that Planck's constant's worth of energy in it, so that's why you have to multiply Planck's constant times the frequency.
我这里用光子这个词,是因为他还总结出光,必须由这些能量包组成，每个能量,包有这个h，普朗克常数代表,里面的能量，所以这就是为什么你们,要用普朗克常数乘以频率。
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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。
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So you know that x-rays are higher frequency than UV light, for example, that means it's also higher energy than UV light, and if you think back to our photoelectric effect experiments, do you remember what type of light we were usually using for those? Does anyone remember?
你们知道，X，射线的频率比紫外光高，这意味着，它的能量也比紫外光要高，那么，请大家回想一下我们的光电效应实验，大家还记得当时我们用的是什么光源吗？,有人记得吗？
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