WHY IS THE SKY BLUE?

Size: px
Start display at page:

Download "WHY IS THE SKY BLUE?"

Transcription

1 WHY IS THE SKY BLUE? by Miles Mathis for the world is hollow and I have touched the sky Abstract: I will show that the current explanation is upside down. In researching this topic, I was surprised to find two different answers from two of the top mouthpieces of current physics. The top answer on a Yahoo search is by Philip Gibbs at the University of California, Riverside 1. It is that blue light is bent more than other colors. Gibbs shows us this illustration:

2 Problem there is that we can move the Sun a few degrees and switch that effect. Just take the Sun above the first guy and he sees an unbent blue ray. The other guy sees a bent red ray. Light must be coming from all directions, not just the direction of the Sun, so this illustration is more than useless, it is misleading. Gibbs then shows it is air molecules, not dust, that do the bending, and he tells us that Einstein calculated in 1911 the scattering by molecules. These equations of Einstein are said to be in agreement with experiment. We are told, the electromagnetic field of the light waves induces electric dipole moments in the molecules. Gibbs then asks the million dollar question: Why not violet? If short wavelengths are bent more than long, then violet should be bent even more than blue, and the sky should be violet. He says it is due to the cones in our eyes. He shows the figure here and says that violet light stimulates red as well, making us see blue. The second top answer is from NASA, and is for kids. I would leave it be for that reason, except that the third 2 and fifth and sixth top answers are strictly the same as this one. All these answers are glosses of the only slightly longer and fuller answer at Wikipedia, which is fourth only because it is titled Diffuse Sky Radiation. That answer is that the blue sky is caused by Rayleigh scattering from molecules. Molecules scatter short wavelengths more than long wavelengths. The Wiki answer is the fullest I found on the web, but even it is short, without the usual attempts to misdirect with large amounts of math or complex theory. We are sent to the page for Rayleigh scattering, but we get one equation and then the whole theory: the shorter wavelength of blue light will scatter more than the longer wavelengths of green and especially red light, giving the sky a blue appearance. Wiki doesn't even bother to spin some yarn to explain why not violet. So let's look at this theory, such as it is. We already have two theories, although they seem to be

3 similar or equivalent at a first glance. Gibbs' theory is that since red light is bent less, it never reaches the ground except near sunset. We get this impression from his illustration, although he never states it explicitly. It is slightly preferable to the scattering hypothesis and the scattering illustration, since it begins to address a smart kid's question: If red is scattered less, wouldn't it just reach the ground directly, with more intensity? So Gibbs draws bending instead of scattering. You see Gibbs has a few dormant scruples left, which makes him try to tweek the horrible answer he has been given from above. He also tries to answer the why not violet? question, although he clearly isn't up to it. His own figure, from eyeball physiology, shows in technicolor detail that the green receptors are also stimulated at violet wavelengths, so why talk about the red and ignore the green? He isn't making any sense. Even if the red were stimulated while the green were not, you still can't build blue from violet plus red, at least not according to the current model. Since the retina is not white, you can't stack these red and violet responses to get blue. That would require red canceling the red in violet. But if the eye is seeing both red and violet, that will make the violet more red, not less red. You can't make violet into blue by adding red in paint mixing, CMY, or RGB. The current model is an RGB model, and when crossing violet light and red light on a white background, you don't get blue. In RGB, you cross red and blue to get magenta. Just the opposite of his implication. But all this is moot, since his figure shows a green response, too. We need to mix red, green, and violet, to address his logic. In RGB, that should give us something quite near white. In CMY, it would give us something nearer black. His whole explanation of why not violet is a wash, and he would have been better to come up with a different dodge. Gibbs' semi-honesty also comes through in his ability to admit that violet is not lacking in the sky. Some have tried to answer why not violet? by claiming that our eyes are not as sensitive to it, or that it is absorbed by the high atmosphere, but Gibbs admits that it must be there, and that we must be sensitive to it, since we see it very well in rainbows. But back to the main question. Forget violet. Can bending or scattering explain why not red? Suppose that atmospheric molecules do scatter blue more or more often than red: does that explain the lack of red in the sky? No. To explain the lack of red, you need to keep red from hitting the ground, so you need to propose that it is bent so much it goes back up, or it is absorbed so much that it never comes down. Neither scattering nor bending does that or can do that, at least not with the current model of light. No smart schoolkid will be fooled by Gibbs replacing scattering with bending, since his question remains: If red is either scattered or bent less or less often, shouldn't it just have a more direct path to the ground? The answer Gibbs is trying to shield or prop up is the scattering answer, which uses Rayleigh scattering as the whole explanation of the blue sky. This is what we get from Wiki: The strong wavelength dependence of the scattering (~λ -4 ) means that blue light is scattered much more readily than red light. In the atmosphere, this results in blue wavelengths being scattered to a greater extent than longer (red) wavelengths, and so one sees blue light coming from all regions of the sky.

4 Notice that Wiki has just interpreted the Rayleigh molecule equation in two different ways. In the first sentence, we are told that the wavelength dependence means that short wavelength light is scattered more readily. In the second sentence, we are told that short wavelengths are scattered to a greater extent. This leads us to ask, Are the short wavelengths supposed to be scattered more often, or at a greater angle? If we study the Rayleigh equation carefully, we find the answer is the angle, not the probability of being scattered. I = I 0 8π 4 α 2 (1 + cos 2 θ)/λ 4 R 2 As you see, we have a representation of the angle, but no representation of the probability of being scattered. The constant α is the polarizability of the molecule, so it cannot vary with the wavelength of the light. The Rayleigh equation gives us an intensity of the scattered light, given an incoming wavelength. In other words, the Rayleigh equation requires the incoming light to be of one wavelength. We can only insert one wavelength into that equation at a time, as you see. We let red light hit a molecule, for example, and the equation tells us how intense the scattered white light will be. This is because the scattering turns the red incoming light into all colors (or, rather, no colors), depending on the angle of scattering. That is what scattering means. That is why the sky is bright instead of dark. If we subtracted out the color problem, we would explain the whiteness of the sky as due to scattering. That is why space is dark: no molecules are scattering, creating the whiteness. We can see this from Wiki, on the page for scattering.

5 Scattering changes or destroys the original wave, as you see. You cannot scatter a wave and keep the wave at the same time. That is having your blue and eating it, too. Despite this, current theory assumes that a wavelength that is blue is scattered, remaining the same blue wavelength; that if anything it gains intensity from the Rayleigh equation; and that it is then reflected down (but not rescattered) by other molecules. Question: why do the first molecules scatter it and the second molecules just reflect it down? How do molecules know when to scatter and when to reflect? Amazing, really, that air molecules can redirect blue so many times without affecting it, but that air molecules cannot do that with red (except at sunset, of course). To see how dishonest all this is, we can study this figure at Wikipedia:

6 Figure showing the more intense scattering of blue light by the atmosphere relative to red light They have created a figure to show what they want to show, although the Rayleigh equation doesn't show it. The figure shows more scattering of blue as a percentage of incoming light, and just in case you missed it, they make the upper part of the figure sky-blue and tell you one more time the conclusion: Rayleigh scattering gives the sky its blue color. They just need a manipulative soundtrack and a nude woman waving a magic wand and the propaganda would be complete. But even the figure contradicts itself, since they feel obligated to cover themselves by giving us a bit of subtext: figure showing more intense scattering of blue light... Wait, they just said in the figure's sidebar that the figure showed more scattering as percentage, and now they are saying the figure shows more intense scattering. But, as I just showed you, the two claims are not the same. The equation does indeed show more intense light scattered from incoming blue, but it doesn't show more scattering of blue as a percentage of all incoming light. Our brain is being massaged here. If we apply the Rayleigh equation to all the different wavelengths, it is just telling us that our scattered white light will be more intense if we start with short wavelength light instead of long wavelength light. And that is just because short wavelength light has more energy to start with. It has a greater frequency, and therefore, according to the Planck relation, it has more energy. More energy supplies more intensity in scattering. So, you see, the Rayleigh equation doesn't tell us a damn thing about color. It doesn't tell us that blue light is scattered more often, or even more. It isn't scattered more, it is scattered at a greater angle, and that just tells us that scattered blue light will cause more intense white light. Current theory assumes that Rayleigh scattering is elastic, since it needs to keep the blue light blue. But there is no proof of that other than the color blue we see. They have no mechanics to explain it or prove it, and since all the math is pushed to fit the data, the math cannot be proof of anything. You see, Rayleigh scattering is even less understood than Compton scattering 7 or Thomson scattering. At least in these two theories of scattering, we have some mention of photons. We have particles acting on eachother: if not colliding, then at least exchanging energies. Beyond that, we have emission and emission fields. But with Rayleigh scattering, we have none of that

7 partial rigor. We just have an equation, derived by slippery means, and then an illogical theory tacked onto it. We are shown a wavelength dependence in the equation, but then the theory and explanation stops. We aren't told how this explains blue reaching the eye but not red. We are told the blue is scattered more than the red; but then what? If the red isn't scattered so much or so often, wouldn't it just continue on down to the ground? And if so, why is it invisible? Current theory has a huge hole in it, and it becomes very conspicuous in this problem of scattering. We are given an equation for scattering but no explanation of it. Nowhere on the web or in any book could I find a definition of this sort of scattering. What is happening mechanically? No one knows, because they will not define the light as either a wave or a particle. We aren't told if the wave is being scattered or if photons are being scattered. All the math and sentences imply it is the wave, but none of the specifics are ever addressed. The quantum mechanical explanation of scattering is currently the Feynman explanation, using sum-overs. In this explanation, Feynman, like non-quantum explainers, mainly avoids any mechanics. Feynman tells us it is photons that are scattered, but he likes to use his little clocks and vectors 8 to solve these problems, and he will not admit that these clocks and vectors track the waves. Clocks are waves. At any rate, this is the nearest we get to a mechanical explanation of photon mechanics, but it is a purposeful misdirection. Feynman and other quantum physicists have told us not to ask mechanical questions, which is convenient for them. Feynman came closest to being able to solve these problems because he allowed himself a math that represented the photon as both wave and particle at the same time. Before that, we have to go all the way back to Maxwell to find someone giving the photons themselves waves (or spins), and Maxwell only tried that for a couple of years before it gave it up. Before Maxwell, we go back to Newton, who tried to give his corpuscles spins (and spins are waves). Both Newton and Maxwell were shouted down or ignored, and since Feynman died quantum physics has ditched his clock method as too visual and mechanical. But treating the photon as both particle and wave is the only way to solve this problem. I have no use for sum-overs or photons with clocks, but we can solve this problem by giving the photon spin. We can solve without throwing out Rayleigh's equation; or Einstein's 1911 calculations, either. We just need a bit more theory. Contemporary theory didn't have quite enough physics to explain it, so they had to fill the gap with bluster and fudge. The truth is, red is actually scattered more than blue, but Rayleigh's equation can't show that by itself. Rayleigh's equation doesn't contain the theory or the variables to tell us what wavelength is scattered the most often, and nothing in current light theory does either. But it turns out that red is scattered more simply because its wavelength is larger. I have shown in other papers 6 that the wavelength of light is not caused or carried or expressed by the wave front or by a group of photons or by any medium. It is caused by each individual photon. Each photon has a tiny local wavelength, caused by spin about an axis, and this local wavelength is stretched out by the speed of the photon. The orbital velocity of the photon is 1/c, and the linear velocity is obviously c, so the local wavelength is stretched out by c 2. That is where the c 2 in Einstein's famous equation comes from.

8 Given that, we see that the individual red photon is bigger than the individual violet photon, at the quantum level. Because it is bigger, it has a slightly larger cross section. So it is more likely to collide with anything, electron or proton or molecule or other particle. Conversely, violet photons are more likely to dodge collision. Yes, violet photons, because they have a smaller wavelength, actually avoid scattering better than red photons. What we see in sky color are photons that haven't been scattered, not photons that have been scattered. As a first rule, the scattered photons make the white, and the unscattered photons make the color. This is also the explanation for how light can arrive with many different wavelengths. The current model cannot show how incoming white light from the Sun can carry all the wavelengths at once. If a wave hits an air molecule in being scattered, how can the wave be red and yellow and green and blue all at once? A wave must have some structure, by definition, and a wave that was green in one place and red in the next wouldn't have any structure. Light is still drawn as a field wave in modern illustrations (in the rare case that these phenomena are illustrated), and a field wave cannot vary its wavelength all over the place. But if each photon can carry the wave, then it is easy to show how white light can carry various colors. If light is not a field wave, then this question answers itself, by simply evaporating. Photons may sort themselves by wavelength, but the energy of the wave is not determined by particle alignment or rowing or fronts or anything else. A single photon can express the wave by itself. Why not violet? Because, to see a violet sky, it would require that violet is never scattered and all other colors are always scattered. That is not logical. We have found that violet is less likely to be scattered, but not that it is never scattered. So the sky color we see is an average of all the unscattered light that reaches us. Some small part is red, a bit more is yellow, a bit more is green, a bit more is blue, and a bit more is violet. We add them all up, and what do we get? We get blue. We get a spectrum weighted by probability toward violet, but not all the way to violet. You will say, But if we are seeing all these colors in the sky, shouldn't the sky be white? All the colors together are white. Well, the sky is a fairly pale blue. So we have a lot of white there, yes. But the sky color we see is unscattered light, not scattered light. So even though it has some components across the spectrum, it is fairly coherent, relative to the scattered light also entering the eye. By coherent, I just mean that it is coming to us in a relatively orderly fashion. It has not been scattered, so it is more orderly than scattered light. The eye reads scattered light as white, but it does not read two (or more) unscattered colors arriving together as white. It is known that the eye reads color relative to other color, and it treats unscattered light like that. We already know that if one source is sending the eye several colors, the eye weighs the colors and averages. That is how it creates blue-grey and brown and so on. Because the sky is heaviest at the violet end and lightest at the red end, the eye averages at blue, then greys it out. The blue part of that is the average wavelength, and the grey part of that is the overlaying of the colors. You will say that the current explanation could steal that last part from me and ditch all the hoodoo about red being bigger than violet. Yes, they could and they probably will. But the truth is they have the mechanics upside down. The blue is not scattered more often, the red is. If the

9 blue were scattered more, the sky would be red. I passed this theory by a mainstream physicist, and his first comment was that if we are seeing unscattered blue, then we should see it only in the direction of the Sun. I found that comment a bit shocking, since to make it you have to assume that light is arriving on the Earth only in a narrow band the width of the visible Sun. I am not aware that anyone thinks that, physicist, artist, or shoe salesman. We all know that the Sun is emitting light spherically, and that the Earth intercepts this light across its whole diameter. Perhaps this physicist meant that light coming from other directions than the visible Sun had to be focused a bit to reach any one eye, but that isn't hard to explain. The Earth's upper atmosphere simply focuses the incoming light, due to its own spherical shape, like a big eyeball. This focusing is very imperfect, simply pulling the light generally toward the surface, but it is enough to account for the light coming from all directions. Yes, the light from the direction of the Sun itself will be the most intense by far, but it is not difficult to explain light coming from all directions. He then said, In that case, I don't see that we need scattering at all. You just explained scattering without scattering. No, I didn't. I explained light being spread across the diameter of the Earth, but that does not negate scattering, or give scattering nothing to do. My mechanism of imperfect focusing is not meant to be a replacement for scattering, and it couldn't possibly create the brightness that scattering creates. Nonetheless, I don't see how it can be denied. Why would the spherical shape of the atmosphere NOT create this focusing of incoming light? The current theory uses this theory of focusing by a sphere to explain rainbows, as when the spherical raindrop deflects light toward its rear center. If the raindrop does it, why wouldn't the Earth's atmosphere? The physicist admitted my point. If that point is admitted, then we only have to show that this focusing does not destroy all possibility of blue light. It doesn't, of course, since we all know that blue light can be reflected or deflected. We then have blue light coming from all directions in the sky (but the least near the horizon). Some of it will be scattered, increasing the brightness of the sky, and some will not. The blue we see is the unscattered blue. We see clear proof I am right if we then ask the standard model why clouds are white. We are told that clouds scatter all the light the same amount via Mie scattering, creating white light. So Mie scattering creates white clouds and Rayleigh scattering creates a blue sky. This despite the fact that the math is basically the same for the two. Both Rayleigh and Mie applied Maxwell's equations to similar problems, only Mie's particles were bigger. In fact, Rayleigh's equations were first applied to spherical particles, same as Mie's. They were then tweeked to account for the fact that air molecules are not spherical or otherwise isotropic. However, this tweeking is not where the wavelength enters the equations. Rayleigh included the wavelength variation even before the equations were tweeked for the anisotropy. Why? Because Rayleigh developed his scattering equations specifically to explain why the sky was blue! He needed a wavelength variation and Mie didn't. The equations were pushed to match data. You can't have large particles that scatter all light the same and small particles that scatter blue

10 more, unless you show some mechanical reason for that difference. Rayleigh couldn't show that reason and neither has anyone else. No one has claimed it is the anisotropy of air molecules that is the cause, although that is the only apparent difference, other than size. They can't do that because, as I said, the Rayleigh equations show wavelength variation even with isotropic molecules. 3 If it is not the anisotropy that causes the wavelength variation, is it the size? We don't know, since the mathematicians won't tell us, but Wiki will admit that, In contrast to Rayleigh scattering, the Mie solution to the scattering problem is valid for all possible ratios of diameter to wavelength. This must mean that the Rayleigh solution is a subset of the Mie solution; and that means that one cannot work in a fundamentally different way than the other. And that means that we have no explanation for why Rayleigh scattering is wavelength dependent and Mie scattering isn't. The explanation is that the sky is blue and clouds are white, which is of course circular. As usual, the theorists try to misdirect us from this realization with a lot of fancy math. We are told that, Quantum mechanical perturbation theory for two-photon elastic processes provides both a powerful and elegant means (e.g.: Craig and Thirunamachandran, 1984) 3 for deriving the Rayleigh equation. But if you honestly believe that a QM perturbation solution will be elegant, you are not paying attention. I suggest you study some QM perturbation solutions and get back to me. What would be truly elegant would be a simple mechanical solution, but QM was forbidden from giving you that by the Copenhagen interpretation, back in the 1920's. Instead, they pile more math on your head to try to keep you from asking for sense. Nowhere in this perturbation solution do they address my question here, as to what is causing the wavelength dependence. The perturbation solution is not more mechanical, it is very much less mechanical. More math is always used to cover less mechanics. We also get sentences like this: The polarizability of a molecule will depend on its orientation relative to the direction of the incident light and, in general, is a tensor of rank 2. 3 Yes, but that is just misdirection. I don't give a flying squirrel what rank the tensor is, I want to know what the polarizability of the molecule has to do with its ability to sort wavelengths. Keep your math in your hat, but tell me how a small sphere or non-sphere can sort wavelengths while a large sphere cannot. Until you can do that, I am going to assume all your math is just used to create the answer you need. To show this pushing of math to force a solution, we may look closer at this page I have been quoting from the University of California at Irving. This author, Chris McLinden, develops the Rayleigh equation as a limiting case of Mie scattering. 4 But since Mie scattering creates white light, he cannot do this without cheating. He imports equations from his Mie page to develop a Rayleigh matrix, and then says, and from equation (2.39), the Rayleigh scattering cross-section is... And we get the Rayleigh equation, complete with the wavelength in the denominator. Unfortunately, there is no equation 2.39 on his website. We assume it is a typo for 3.39, but neither equation 3.39 nor any of the equations around it have any wavelength variables in them. How could they, since equation 3.39 is on his Mie scattering page: Mie scattering is not wavelength dependent! Where did the wavelength come from? We cannot dismiss this as just an

11 unimportant oversight or recent typo, since this is a university website that has been up for over a decade, and that scores number five on a websearch for Mie scattering. At number five on a search for Rayleigh scattering, we pull up a website by Philip Laven 5 that clarifies this a bit. There we find that the scattering angle is proportional to x 3, and that x = 2πr/λ. But r here is the radius of the scattering sphere. So, again, we have to ask by what mechanics a small sphere shows a dependence between r and λ, and a larger sphere does not. And, again, Mr. Laven has nothing to say about it. He has more fancy graphs than Wikipedia itself, but no more mechanics. Like Wiki, he has zero mechanics. Notice that I can explain white clouds without contradicting myself. I have said that all scattering creates white light, and clouds simply scatter more. Therefore they are whiter. Because the particles in clouds are much larger than molecules, neither the blue light nor the red light can dodge them. All the wavelengths are scattered, destroying the blue. If clouds have any color, it tends to be a light violet. This also confirms my theory, since violet is the smallest visible photon. If any photons can dodge the scattering, it is violet. If any color gets through, it will be violet, not blue. I will be told that clouds tend to go to grey, but those are shadows. The greys are always on the dark sides of clouds, when clouds are dense enough to scatter most light up or sideways. The grey is not color, it is relative darkness. Current theory is also contradictory in its explanation of why the Sun appears yellow. Wiki tells us: Conversely, glancing toward the sun, the colors that were not scattered away the longer wavelengths such as red and yellow light are visible, giving the sun itself a slightly yellowish hue. So we see yellow because it is not scattered, and blue because it is? That doesn't make any sense at all. Current theory tells us that the blue is coming to us indirectly, and the yellow is coming directly, but we already know that isn't how light works. Scattered light coming

12 indirectly from all directions is seen as white light. This is because as light is scattered, its energy is affected by the angle of scattering. Molecules scatter photons at any number of different angles, and blue photons that are scattered are no longer seen as blue. You can't scatter light in all directions and then claim it is still blue. I have already shown why we see blue, and it isn't because blue light is scattered, staying blue. Just think of it this way: assume current theory is correct, and work back from your eye. Say you are receiving blue from all parts of the sky, except from the direction of the Sun. That means you are receiving blue from all different angles. Go up into the sky, to one molecule that is scattering the light to you. There is an angle at that molecule between you and the Sun. The molecule supposedly deflected the blue photon from the Sun to you, at that angle. Now go to all the other molecules that are doing the same thing. The angle is different for each one. How can the angle be any possible angle, and the light stay blue? According to this theory, any angle of scattering is blue, and no angle of scattering is red. Impossible. We can see other big problems with current theory. Current theory tells us that yellow light from the Sun is not scattered, and that is why we see a yellow Sun. But in the next sentence, the same theory tells us that in space, the Sun is white. Well, if the light from the Sun is actually white, and the light we see in the line of the Sun is unscattered, then we should see the Sun as white here on Earth, too. They just told us the light was coming directly to our eye, and was not scattered. If it isn't scattered, why is it changed? Why isn't it white? They would have to answer that the violet, blue, green, and red is scattered, leaving only the yellow unscattered. But in that case they have contradicted themselves. In the line of the Sun, we don't see blue because it is scattered away. But everywhere else, we do see blue because it is scattered away. In that case, we have to ask again, Do we see color because it scattered, or because it is unscattered? You have to make up your mind. You can't have it both ways. According to current theory, if we see blue because it is scattered, then we should see yellow in the direction of the Sun because it is also scattered. But if that were true, we would have to ask why molecules in line with the Sun act differently. Why do molecules in the line of the Sun scatter yellow? Or, going back to the previous theory, why would molecules in the line of the Sun scatter everything except yellow? It has to be one or the other, but both are illogical. Molecules in the line of the Sun cannot act differently than molecules in other parts of the sky. The current answer is that molecules in the line of the Sun scatter shorter wavelengths, just like everywhere else, but that is a fudge, since the Sun only looks yellow: it does not look green or red. If the sky scatters blue, then the Sun should look red, green, and yellow. Current theory tries to average these three into yellow, but according to current theory, neither light nor the eye works that way. If we are seeing red, green, and yellow from a source, we will not average that into yellow, we will combine it into brown or grey. Yes, if we are receiving much more yellow than green and red, we will see a greyed out yellow, but that is not the situation with the Sun. The Sun we see is supposed to be white minus violet, and white minus violet is not yellow. In other words, my average worked above, since I was not averaging three equal parts. I was averaging large amounts of blue and violet with much smaller amounts of green, yellow, and

13 red. This gave me an average of a slightly greyed out blue. But the current model is trying to average equal parts of red, yellow and green to get yellow. Even if they steal my averaging method, they still can't get yellow from that. They get brown or grey. And, besides, they can't use my averaging method, because their theory is not a color averaging theory. Their theory is a physiological RGB theory, where you would cross red and green to get yellow. If you add yellow to that, you get a double saturated yellow. They should predict a very yellow Sun, not a pale yellow Sun. The reason we see a Sun that appears slightly yellow is mainly because it is next to a blue sky. It is an optical illusion. It is related to this optical illusion called moth eggs. The eggs are actually white, but appear yellow against this background of blue and green. You will say that the sky is not green, but I have shown that it contains some unscattered green, just as this illusion does. This is why the Sun looks yellower in the summer: the green of the trees and landscape reflects off the sky, adding green to the background the eye sees. On a background of green and blue, white will appear pale yellow. Another reason we think the Sun is yellower than it is concerns the afterimage. We can only glance at the Sun for a split second. If you try it you will see that the yellow is in the afterimage, burned in the retina around the Sun. You don't really see a yellow Sun, you see a yellow afterimage. If you block the circle of the Sun and just look at the sky around the Sun, you will see that the yellow is mostly a myth. We are mistaking bright warm white for yellow. The white looks warm because it is surrounded by cool blue. Even the yellow in the afterimage is false, since it is also caused by the original blue response. It is the retina's response to very white light on a blue background. The retina always tries to supply the contrary color, for reasons still unknown; and the brighter the light, the more the retina supplies the contrary. The yellow circle is just this response to blue: that is why it is only on the edge of the Sun, where the blue meets the white. Then why is the sky red at sunset? If the current model is upside down, then they must be wrong about that, too. Yes, they are. They say that the blue is scattered less then, but it is actually

14 scattered more. The dust particles that do the scattering at sunset are bigger than atmospheric molecules, so the violet and blue light can't dodge it as well. The violet light is therefore scattered almost as much as the red. The current explanation is that red at sunset is caused by particles at low altitudes, from dust, pollution, or other causes. Unfortunately, Rayleigh scattering (and Tyndall scattering, which Gibbs mentions on his page) is not different for larger particles. The Rayleigh equation for particles larger than molecules also has the wavelength variable in the denominator, which means dust particles would not scatter red preferentially over blue, according to current theory. Given current theory, dust should also scatter blue more or more often, because λ 4 is in the denominator. These people do not seem to be able to read an equation: they think they can push it any way they like, scattering blue in one case and red in another. But they are correct that the angle to the Sun is important. At sunrise and sunset, we see red due to reflection from clouds and dust, not scattering. That is, we see a single bounce, at a specific angle. To see red, our eye has to be at a very specific angle to the cloud or dust. Even some editors at Wiki seem to understand this, since at the Tyndall Effect page, we find The term "Tyndall effect" is sometimes applied to light scattering by macroscopic particles such as dust in the air. However, this phenomenon is more like reflection, not scattering, as the macroscopic particles become clearly visible in the process. There it is, Wiki contradicts Gibbs, and actually gets something right. We know that the red must be caused by reflection, because we get red in the area of sky opposite the Sun as well as the area toward the Sun. Clouds at the right angle can reflect red back to us. You will say, If red is scattered more by the Rayleigh equation, then it should be scattered a lot by dust and the dense atmosphere at low altitudes. So it should be scattered massively in this situation. Yes, and it is. I didn't say that red wasn't scattered at sunset. I said that the red we see isn't caused by this scattering. The phenomenon of red sunsets is not caused by scattering. The red we don't see is caused by scattering. The red we do see is unscattered light (of any original wavelength) that is reflected to us at the right angle Mathis, Miles. Planck's Constant and Quantization Mathis, Miles. The Compton Effect, Duality, and the Klein-Nishina formula Mathis, Miles. Three Problems Solved Mechanically

15

The Magnetic Moments of Proton, Neutron and Electron

The Magnetic Moments of Proton, Neutron and Electron return to updates The Magnetic Moments of Proton, Neutron and Electron by Miles Mathis First published March 31, 2013 To start this paper, we will look closely at the definition of magnetic moment. Many

More information

The Electromagnetic Spectrum

The Electromagnetic Spectrum The Electromagnetic Spectrum 1 Look around you. What do you see? You might say "people, desks, and papers." What you really see is light bouncing off people, desks, and papers. You can only see objects

More information

The Photoelectric Effect

The Photoelectric Effect The Photoelectric Effect http://www.colorado.edu/physics/2000/quantumzone/photoelectric.html 1 of 3 10/5/2007 8:36 AM The Photoelectric Effect What's the photoelectric effect? It's been determined experimentally

More information

Atomic Structure. AGEN-689: Advances in Food Engineering

Atomic Structure. AGEN-689: Advances in Food Engineering Atomic Structure AGEN-689: Advances in Food Engineering Ionian scholars- 15 th century Some ancient Greek philosophers speculated that everything might be made of little chunks they called "atoms." The

More information

April 17. Physics 272. Spring Prof. Philip von Doetinchem

April 17. Physics 272. Spring Prof. Philip von Doetinchem Physics 272 April 17 Spring 2014 http://www.phys.hawaii.edu/~philipvd/pvd_14_spring_272_uhm.html Prof. Philip von Doetinchem philipvd@hawaii.edu Phys272 - Spring 14 - von Doetinchem - 328 Standing electromagnetic

More information

Alternating Current. and Inductance. by Miles Mathis. First published June 16, 2014

Alternating Current. and Inductance. by Miles Mathis. First published June 16, 2014 return to updates Alternating Current and Inductance First published June 16, 2014 by Miles Mathis In previous papers on electric charge and the battery circuit and other problems, we have seen that mainstream

More information

Color Part I. (The two items we can determine: a. How bright is the light is. b. What color the light is.)

Color Part I. (The two items we can determine: a. How bright is the light is. b. What color the light is.) Color Part I Name Color is one of the most important pieces of information scientists have used for all time. In space it is one of only two pieces of information we can collect without sending probes

More information

Sky Colours. Math 309 Spring 2004 Ryan Leslie

Sky Colours. Math 309 Spring 2004 Ryan Leslie Sky Colours Math 309 Spring 2004 Ryan Leslie Overview Why the sky is blue Colour of sky during sunsets and sunrises Polarization of light affecting blueness Atmospheric effects Why the sailor s adage works

More information

More on the Golden Ratio and the Fibonacci series

More on the Golden Ratio and the Fibonacci series return to updates More on the Golden Ratio and the Fibonacci series by Miles Mathis A couple of years ago I wrote a long paper on the golden ratio, showing how the unified field caused a field constraint

More information

Processes affecting propagation of electromagnetic radiation (light)

Processes affecting propagation of electromagnetic radiation (light) Chapter 4 Light and Color, and Atmospheric Optics Useful links: http://www.atoptics.co.uk/ http://www.gi.alaska.edu/atmossci/links.mainpage/arcti c_optical.html Processes affecting propagation of electromagnetic

More information

Chapter 5 Review Clickers. The Cosmic Perspective Seventh Edition. Light and Matter: Reading Messages from the Cosmos Pearson Education, Inc.

Chapter 5 Review Clickers. The Cosmic Perspective Seventh Edition. Light and Matter: Reading Messages from the Cosmos Pearson Education, Inc. Review Clickers The Cosmic Perspective Seventh Edition Light and Matter: Reading Messages from the Cosmos When light approaches matter, it can a) be absorbed by the atoms in the matter. b) be transmitted

More information

AP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light

AP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light AP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light Name: Period: Date: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Reflection,

More information

STOP for science. Light is a wave. Like waves in water, it can be characterized by a wavelength.

STOP for science. Light is a wave. Like waves in water, it can be characterized by a wavelength. INTRODUCTION Most students have encountered rainbows, either spotting them directly on those special days when the raindrops fall while the Sun still finds cloudless regions to peek through, or at least

More information

Instructor So white light coming from a light bulb or from the sun can be separated into the colors of the rainbow.

Instructor So white light coming from a light bulb or from the sun can be separated into the colors of the rainbow. Physics 1303 Color Today, you have a lot to learn about colors, from why blue and yellow don t make green, to why the earth s sky is blue and the moon s sky is black. Let s start our study of colors with

More information

Chapter 16 Light Waves and Color

Chapter 16 Light Waves and Color Chapter 16 Light Waves and Color What causes color? What causes reflection? What causes color? What causes reflection? Why does a soap film display different colors? How do we see color? Why is the sky

More information

Light in different media

Light in different media Light in different media A short review Reflection of light: Angle of incidence = Angle of reflection Refraction of light: Snell s law Refraction of light Total internal reflection For some critical angle

More information

Properties of Light. electromagnetic waves. This energy is both magnetic and electrical.

Properties of Light. electromagnetic waves. This energy is both magnetic and electrical. 1 Light is one form of energy that travels in electromagnetic waves. This energy is both magnetic and electrical. 2 There are many different types of electromagnetic (EM) waves. Most of them cannot be

More information

1. Introduction to Fundamentals

1. Introduction to Fundamentals Section 1.1 What is Remote Sensing? Page 5 1. Introduction to Fundamentals 1.1 What is Remote Sensing? So, what exactly is remote sensing? For the purposes of this tutorial, we will use the following definition:

More information

Light Waves. Today s Topics Color Addition - Light Color Subtraction Pigment Color of water Color of the Sky

Light Waves. Today s Topics Color Addition - Light Color Subtraction Pigment Color of water Color of the Sky Light Waves Today s Topics Color Addition - Light Color Subtraction Pigment Color of water Color of the Sky Additive Color Which of the following is NOT a primary color of light Blue Yellow Red Green Which

More information

Announcements. Homework 6 due Thursday

Announcements. Homework 6 due Thursday Tuesday, October 23rd. Announcements. Homework 6 due Thursday Lecture #13-1 Lecture #13-2 Highlights that although natural gas is less bad for the environment than coal, it is much more expensive. (Although

More information

THE ELECTROMAGNETIC SPECTRUM

THE ELECTROMAGNETIC SPECTRUM THE ELECTROMAGNETIC SPECTRUM Electromagnetic radiation comes in a large range of frequencies and wavelengths. The range is referred to as "the electromagnetic spectrum". To give a few examples: in the

More information

Black Body Radiation & Planck's Hypothesis

Black Body Radiation & Planck's Hypothesis Black Body Radiation & Planck's Hypothesis In physics, a black body is an idealized object that absorbs all electromagnetic radiation that falls on it. No electromagnetic radiation passes through it and

More information

Electromagnetic Radiation Spectrum

Electromagnetic Radiation Spectrum Electromagnetic Radiation scillating electric and magnetic fields propagate through space Virtually all energy exchange between the Earth and the rest of the Universe is by electromagnetic radiation Most

More information

Waves Sound and Light

Waves Sound and Light Waves Sound and Light r2 c:\files\courses\1710\spr12\wavetrans.doc Ron Robertson The Nature of Waves Waves are a type of energy transmission that results from a periodic disturbance (vibration). They are

More information

Making Waves. A vibrating source creates waves. A vibrating electrically charged rod will create a set of electromagnetic waves.

Making Waves. A vibrating source creates waves. A vibrating electrically charged rod will create a set of electromagnetic waves. Making Waves A vibrating source creates waves. A vibrating electrically charged rod will create a set of electromagnetic waves. Making Electromagnetic Waves Actually, any device that runs on alternating

More information

Chapter 27 Color. 04/14/04 Dr. Jie Zou PHY 3050G Department of Physics

Chapter 27 Color. 04/14/04 Dr. Jie Zou PHY 3050G Department of Physics Chapter 27 Color Selective reflection Selective transmission Mixing colored light Why the sky is blue Why sunsets are red Why clouds are white Why water is greenish blue 1 Color The colors we see depend

More information

The Electromagnetic Spectrum

The Electromagnetic Spectrum Light as Information Bearer REVIEW We can separate light into its different wavelengths (spectrum). AST 105 Intro Astronomy The Solar System MIDTERM II: Tuesday, April 5 [covering Lectures 10 through 16]

More information

Digital Image Processing. Prof. P.K. Biswas. Department of Electronics & Electrical Communication Engineering

Digital Image Processing. Prof. P.K. Biswas. Department of Electronics & Electrical Communication Engineering Digital Image Processing Prof. P.K. Biswas Department of Electronics & Electrical Communication Engineering Indian Institute of Technology, Kharagpur Lecture - 27 Colour Image Processing II Hello, welcome

More information

Turn off all electronic devices

Turn off all electronic devices Sunlight 1 Sunlight 2 Observations about Sunlight Sunlight Sunlight appears whiter than most light Sunlight makes the sky appear blue Sunlight becomes redder at sunrise and sunset It reflects from many

More information

Physics 1230 Light and Color : Exam #3

Physics 1230 Light and Color : Exam #3 Physics 1230 Light and Color : Exam #3 Your Last Name Your First & Middle Name General information: This exam will be worth 100 points. There are 15 multiple choice questions worth 3 points each (part

More information

Name Class Date. spectrum. White is not a color, but is a combination of all colors. Black is not a color; it is the absence of all light.

Name Class Date. spectrum. White is not a color, but is a combination of all colors. Black is not a color; it is the absence of all light. Exercises 28.1 The Spectrum (pages 555 556) 1. Isaac Newton was the first person to do a systematic study of color. 2. Circle the letter of each statement that is true about Newton s study of color. a.

More information

COLLEGE PHYSICS. Chapter 29 INTRODUCTION TO QUANTUM PHYSICS

COLLEGE PHYSICS. Chapter 29 INTRODUCTION TO QUANTUM PHYSICS COLLEGE PHYSICS Chapter 29 INTRODUCTION TO QUANTUM PHYSICS Quantization: Planck s Hypothesis An ideal blackbody absorbs all incoming radiation and re-emits it in a spectrum that depends only on temperature.

More information

Atmospheric Optical Phenomena

Atmospheric Optical Phenomena Atmospheric Optical Phenomena Atmospheric Optical Phenomena are produced by the reflection, refraction, dispersion and scattering / diffusion of rays of sunlight. These principles in physics explain commonly

More information

14.2 Color. Where does color come from? Chapter 14

14.2 Color. Where does color come from? Chapter 14 Color adds much richness to the world. The rainbow of colors our eyes can see ranges from deep red, through the yellows and greens, up to blue and violet. Just as we hear different frequencies of sound

More information

What Wavelength Goes With a Color?

What Wavelength Goes With a Color? What Wavelength Goes With a Color? Our eyes are sensitive to light which lies in a very small region of the electromagnetic spectrum labeled "visible light". This "visible light" corresponds to a wavelength

More information

Today: Chapter 27 (Color) Teacher evaluations

Today: Chapter 27 (Color) Teacher evaluations Please pick up your 2nd midterm from front of class if you haven t already Looking ahead: Tues May 22: Final Exam, 11.30am 1.30pm, 65 multiple-choice questions Final Exam is cumulative i.e. Chs. 2, 3,

More information

Properties of Light By Cindy Grigg

Properties of Light By Cindy Grigg Properties of Light By Cindy Grigg 1 Light is one form of energy that travels in electromagnetic waves. This energy is both magnetic and electrical. 2 There are many different types of electromagnetic

More information

Name Date Class. By studying the Vocabulary and Notes listed for each section below, you can gain a better understanding of this chapter.

Name Date Class. By studying the Vocabulary and Notes listed for each section below, you can gain a better understanding of this chapter. CHAPTER 22 VOCABULARY & NOTES WORKSHEET The Nature of Light By studying the Vocabulary and Notes listed for each section below, you can gain a better understanding of this chapter. SECTION 1 Vocabulary

More information

Chapter 28. Atomic Physics

Chapter 28. Atomic Physics Chapter 28 Atomic Physics Sir Joseph John Thomson J. J. Thomson 1856-1940 Discovered the electron Did extensive work with cathode ray deflections 1906 Nobel Prize for discovery of electron Early Models

More information

Chapter 27 Practice Problems, Review, and Assessment. 2. A photon s energy is 2.03 ev. What is the photon s wavelength? SOLUTION:

Chapter 27 Practice Problems, Review, and Assessment. 2. A photon s energy is 2.03 ev. What is the photon s wavelength? SOLUTION: Section 1 A Particle Model of Waves: Practice Problems Use E = 1240 ev nm/λ to solve the following problems. 1. What is a photon s energy if the photon s wavelength is 515 nm? 2. A photon s energy is 2.03

More information

The Evolution of the Atom

The Evolution of the Atom The Evolution of the Atom 1808: Dalton s model of the atom was the billiard ball model. He thought the atom was a solid, indivisible sphere. Atoms of each element were identical in mass and their properties.

More information

HOW a BATTERY CIRCUIT WORKS

HOW a BATTERY CIRCUIT WORKS return to updates HOW a BATTERY CIRCUIT WORKS by Miles Mathis First posted May 16, 2011 A reader sent me a link to an article from 2002 by Ian Sefton of University of Sydney, who tries to explain how a

More information

Section 3. The Size of a Nucleus: How Big Is Small? What Do You See? What Do You Think? Investigate. Learning Outcomes

Section 3. The Size of a Nucleus: How Big Is Small? What Do You See? What Do You Think? Investigate. Learning Outcomes Section 3 The Size of a Nucleus: How Big Is Small? Section 3 The Size of a Nucleus: How Big Is Small? What Do You See? Learning Outcomes What Do You Think? In this section, you will Everyone has heard

More information

Chapter 29 Particles and Waves

Chapter 29 Particles and Waves Chapter 29 PARTICLES AND WAVES PREVIEW A photon is the smallest particle of light, and has an energy which is proportional to its frequency. The photon nature of light is the principle behind the photoelectric

More information

Light, Light Bulbs and the Electromagnetic Spectrum

Light, Light Bulbs and the Electromagnetic Spectrum Light, Light Bulbs and the Electromagnetic Spectrum Spectrum The different wavelengths of electromagnetic waves present in visible light correspond to what we see as different colours. Electromagnetic

More information

Lecture 34 Chapter 29 Wave Properties of Light (Beyond Refraction)

Lecture 34 Chapter 29 Wave Properties of Light (Beyond Refraction) Lecture 34 Chapter 29 Wave Properties of Light (Beyond Refraction) 18-Nov-10 Light Wavefronts and Rays Circular wavefronts (could be electric field wave crests) Rays - show direction of wave motion. Plane

More information

Physics of Color GBI Knowledge Center

Physics of Color GBI Knowledge Center Physics of Color GBI Knowledge Center Technically speaking, colors are the way our brain, by use of our eyes, interprets electromagnetic radiation of a wavelength within the visible spectrum. Visible light

More information

Home Lab 6 Color, Waves, and Dispersion

Home Lab 6 Color, Waves, and Dispersion 1 Home Lab 6 Color, Waves, and Dispersion Overview: Visible light is light that can be perceived by the human eye. When you look at the visible light of the sun, it appears to be colorless, which we call

More information

AST1100 Lecture Notes

AST1100 Lecture Notes AST1100 Lecture Notes 4 Stellar orbits and dark matter 1 Using Kepler s laws for stars orbiting the center of a galaxy We will now use Kepler s laws of gravitation on much larger scales. We will study

More information

Quantization of Energy

Quantization of Energy Quantization of Energy Failures of Classical mechanics Black Body Radiation: WHAT IS BLACK BODY? A black body is a theoretical object that absorbs 100% of the radiation that hits it. Therefore it reflects

More information

Light - Geometric Optics. lecture notes and demonstrations

Light - Geometric Optics. lecture notes and demonstrations Light - Geometric Optics Nature of light Reflection Refraction Dispersion A. Karle Physics 202 Nov. 20, 2007 Chapter 35 Total internal reflection lecture notes and demonstrations Demonstrations: Speed

More information

1. Separation is easy with a magnet (try it and be amazed!).

1. Separation is easy with a magnet (try it and be amazed!). EXERCISES 1. Separation is easy with a magnet (try it and be amazed!). 2. All magnetism originates in moving electric charges. For an electron there is magnetism associated with its spin about its own

More information

CHAPTER 5 COLLISIONS

CHAPTER 5 COLLISIONS CHAPTER 5 COLLISIONS 5 Introduction In this chapter on collisions, we shall have occasion to distinguish between elastic and inelastic collisions An elastic collision is one in which there is no loss of

More information

Chapter 30 Quantum Physics

Chapter 30 Quantum Physics Chapter 30 Quantum Physics Units of Chapter 30 Blackbody Radiation and Planck s Photons and the Photoelectric Effect The Mass and Momentum of a Photon Photon Scattering and the Compton Effect Units of

More information

Thomson and Rayleigh Scattering

Thomson and Rayleigh Scattering Thomson and Rayleigh Scattering Initial questions: What produces the shapes of emission and absorption lines? What information can we get from them regarding the environment or other conditions? In this

More information

Color Properties of color. Color- an element derived from reflected light. If it were not for light, we would have no color

Color Properties of color. Color- an element derived from reflected light. If it were not for light, we would have no color Most Expressive element of art Is powerful Can show emotion Color Properties of color Color- an element derived from reflected light If it were not for light, we would have no color White light from the

More information

4.5 Orbits, Tides, and the Acceleration of Gravity

4.5 Orbits, Tides, and the Acceleration of Gravity 4.5 Orbits, Tides, and the Acceleration of Gravity Our goals for learning: How do gravity and energy together allow us to understand orbits? How does gravity cause tides? Why do all objects fall at the

More information

AST1100 Lecture Notes

AST1100 Lecture Notes AST1100 Lecture Notes 18: General Relativity: Gravitational lensing 1 Motion of light in Schwarzschild spacetime There is one huge difference between Newton s and Einstein s theory of gravity. In the Einstein

More information

Optics Nature of Light Light is a transverse wave. An electric field and a magnetic field change orthogonally to the direction of the light wave.

Optics Nature of Light Light is a transverse wave. An electric field and a magnetic field change orthogonally to the direction of the light wave. Optics Nature of Light Light is a transverse wave. An electric field and a magnetic field change orthogonally to the direction of the light wave. The electromagnetic radiation does not require a medium

More information

Is there life in space? Activity 2: Moving Stars and Their Planets

Is there life in space? Activity 2: Moving Stars and Their Planets Is there life in space? Activity 2: Moving Stars and Their Planets Overview In this activity, students are introduced to the wobble-method of detecting planets. The activity starts with an introduction

More information

Section 18.1 Electromagnetic Waves (pages )

Section 18.1 Electromagnetic Waves (pages ) Name Class Date Section 18.1 Electromagnetic Waves (pages 532 538) This section describes the characteristics of electromagnetic waves. Reading Strategy (page 532) Comparing and Contrasting As you read

More information

Solar and Terrestrial Radiation

Solar and Terrestrial Radiation Solar and Terrestrial Radiation I Heat and Temperature A. 1. A form of. 2. The total of all the atoms and molecules of a substance 3. Heat always moves from a temperature body to a temperature body. B.

More information

LIGHT AND ELECTROMAGNETIC RADIATION

LIGHT AND ELECTROMAGNETIC RADIATION LIGHT AND ELECTROMAGNETIC RADIATION Light is a Wave Light is a wave motion of radiation energy in space. We can characterize a wave by three numbers: - wavelength - frequency - speed Shown here is precisely

More information

Physics 2426 Engineering Physics II Instructor: McGraw Review Questions -Final Exam

Physics 2426 Engineering Physics II Instructor: McGraw Review Questions -Final Exam Physics 2426 Engineering Physics II Instructor: McGraw Review Questions -Final Exam 1. The photon energy for light of wavelength 500 nm is approximately A) 1.77 ev B) 3.10 ev C) 6.20 ev D) 2.48 ev E) 5.46

More information

Abstract. eye hinted what the spectrum would look like. Mercury s gas tube color was very blue, and

Abstract. eye hinted what the spectrum would look like. Mercury s gas tube color was very blue, and Abstract The purpose of this lab was to further our understanding of atomic structure and its relation to the production of light. To do this we used different spectrometers to look at the color spectrum

More information

Science Summary on Light

Science Summary on Light Science Summary on Light Lauren Murray SME 301, Section 3 Misconception Incorrect: We see objects only if they reflect light. False. Correct: We can see objects that do not reflect light, but only if they

More information

PS-7.2 Compare the nature and properties of transverse and longitudinal/compressional mechanical waves.

PS-7.2 Compare the nature and properties of transverse and longitudinal/compressional mechanical waves. PS-7.1 Illustrate ways that the energy of waves is transferred by interaction with matter (including transverse and longitudinal /compressional waves). Understand that a wave is a repeating disturbance

More information

Astronomy 110 Homework #05 Assigned: 02/13/2007 Due: 02/20/2007. Name: (Answer Key)

Astronomy 110 Homework #05 Assigned: 02/13/2007 Due: 02/20/2007. Name: (Answer Key) Astronomy 110 Homework #05 Assigned: 02/13/2007 Due: 02/20/2007 Name: (Answer Key) Directions: Listed below are twenty (20) multiple-choice questions based on the material covered by the lectures thus

More information

6. What is the approximate angular diameter of the Sun in arcseconds? (d) 1860

6. What is the approximate angular diameter of the Sun in arcseconds? (d) 1860 ASTR 1020 Stellar and Galactic Astronomy Professor Caillault Fall 2009 Semester Exam 1 Multiple Choice Answers (Each multiple choice question is worth 1.5 points) 1. The number of degrees in a full circle

More information

Astronomy 110 Homework #11 Assigned: 04/17/2007 Due: 04/24/2007. Name: (Answer Key)

Astronomy 110 Homework #11 Assigned: 04/17/2007 Due: 04/24/2007. Name: (Answer Key) Astronomy 110 Homework #11 Assigned: 04/17/2007 Due: 04/24/2007 Name: (Answer Key) Directions: Listed below are twenty (20) multiple-choice questions based on the material covered by the lectures thus

More information

Student. Understanding of the Photon Concept: Faculty Expectations. Gordon J. Aubrecht, II and James H. Stith

Student. Understanding of the Photon Concept: Faculty Expectations. Gordon J. Aubrecht, II and James H. Stith Student Understanding of the Photon Concept: Faculty Expectations Gordon J. Aubrecht, II and James H. Stith Department of Physics, Ohio State University Supported by NSF grant GER 9553460 Student Understanding

More information

Chapter 17: Light and Image Formation

Chapter 17: Light and Image Formation Chapter 17: Light and Image Formation 1. When light enters a medium with a higher index of refraction it is A. absorbed. B. bent away from the normal. C. bent towards from the normal. D. continues in the

More information

Chapter 5. Electronic Structure of the Atom

Chapter 5. Electronic Structure of the Atom Chapter 5 Electronic Structure of the Atom Rutherford s Model Discovered the nucleus Small dense and positive Electrons moved around in Electron cloud Bohr s Model Why don t the electrons fall into the

More information

Photon. ~ Quantum of Energy ~ - Light as Waves - Light as Particles. Photoelectric Effect - photon energy. Compton Effect - photon momentum

Photon. ~ Quantum of Energy ~ - Light as Waves - Light as Particles. Photoelectric Effect - photon energy. Compton Effect - photon momentum Photon ~ Quantum of Energy ~ Outline - Light as Waves - Light as Particles. Photoelectric Effect - photon energy. Compton Effect - photon momentum In physics, a quantum is the minimum unit of any physical

More information

Modern Physics P a g e 1 AP Physics B

Modern Physics P a g e 1 AP Physics B 1. Which color of light emitted from an atom would be associated with the greatest change in energy of the atom? (A) Blue (B) Green (C) Red (D) Violet (E) Yellow Questions 2-3 relate to photoelectric effect

More information

CHAPTER 4 Lectures The Global Energy System

CHAPTER 4 Lectures The Global Energy System CHAPTER 4 Lectures 05-09 The Global Energy System I. Electromagnetic Radiation: This form of energy is emitted by all objects. Light and radiant heat are two familiar examples. Light is radiation that

More information

Chapter 4 Atomic Structure

Chapter 4 Atomic Structure Chapter 4 Atomic Structure 4.1 The Nuclear Atom J. J. Thomson found electrons in atoms (1897) by extracting them from a gaseous discharge and bending them in magnetic fields. This let him find their charge/mass

More information

Chapter 3. Electromagnetic Theory, Photons. and Light. Lecture 7

Chapter 3. Electromagnetic Theory, Photons. and Light. Lecture 7 Lecture 7 Chapter 3 Electromagnetic Theory, Photons. and Light Sources of light Emission of light by atoms The electromagnetic spectrum see supplementary material Light in bulk matter and dispersion Sources

More information

Electromagnetic Radiation (EMR) and Remote Sensing

Electromagnetic Radiation (EMR) and Remote Sensing Electromagnetic Radiation (EMR) and Remote Sensing 1 Atmosphere Anything missing in between? Electromagnetic Radiation (EMR) is radiated by atomic particles at the source (the Sun), propagates through

More information

Name Date Class ELECTRONS IN ATOMS

Name Date Class ELECTRONS IN ATOMS Name _ Date Class 5 ELECTRONS IN ATOMS SECTION 5.1 MODELS OF THE ATOM (pages 127 132) This section summarizes the development of atomic theory. It also explains the significance of quantized energies of

More information

Physics Open House. Faraday's Law and EM Waves Change in the magnetic field strength in coils generates a current. Electromagnetic Radiation

Physics Open House. Faraday's Law and EM Waves Change in the magnetic field strength in coils generates a current. Electromagnetic Radiation Electromagnetic Radiation (How we get most of our information about the cosmos) Examples of electromagnetic radiation: Light Infrared Ultraviolet Microwaves AM radio FM radio TV signals Cell phone signals

More information

ABC Math Student Copy

ABC Math Student Copy Page 1 of 8 Line Spectra Physics Week 15(Sem. 2) Name The Atom Chapter Summary From the last section, we know that all objects emit electromagnetic waves. For a solid object, such as the filament of a

More information

THE NATURE OF LIGHT AND COLOR

THE NATURE OF LIGHT AND COLOR THE NATURE OF LIGHT AND COLOR THE PHYSICS OF LIGHT Electromagnetic radiation travels through space as electric energy and magnetic energy. At times the energy acts like a wave and at other times it acts

More information

Atoms, Electrons, and Periodic Trends C h a p t e r P r e v i e w P r e r e q u i s i t e C o n c e p t s a n d S k i l l s Atoms and e ect

Atoms, Electrons, and Periodic Trends C h a p t e r P r e v i e w P r e r e q u i s i t e C o n c e p t s a n d S k i l l s Atoms and e ect Atoms and electrons The northern lights, also called the aurora borealis, it the result of streams of protons and electrons from the Sun. When the electrons interact with gaseous atoms in Earth s upper

More information

So, you want to make a photo-realistic rendering of the Earth from orbit, eh? And you want it to look just like what astronauts see from the shuttle

So, you want to make a photo-realistic rendering of the Earth from orbit, eh? And you want it to look just like what astronauts see from the shuttle So, you want to make a photo-realistic rendering of the Earth from orbit, eh? And you want it to look just like what astronauts see from the shuttle or ISS (International Space Station). No problem. Just

More information

Assignment 10. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

Assignment 10. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. Assignment 10 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Where would you look for the youngest stars in the Milky Way Galaxy? a. in

More information

AST 103 Blackbody Radiation

AST 103 Blackbody Radiation AST 103 Blackbody Radiation Prof. Ken Nagamine UNLV 1 Analyzing Starlight What can looking at an object s spectrum tell us about the object? 2 Analyzing Starlight What can an object s spectrum tell us

More information

Chapter 5. Electrons in Atoms

Chapter 5. Electrons in Atoms Chapter 5 Electrons in Atoms Ernest Rutherford s Model Discovered dense positive piece at the center of the atom- nucleus Electrons would surround and move around it, like planets around the sun Atom is

More information

Smiley Radio Telescope Lab 4 Radio Waves from the Galaxy

Smiley Radio Telescope Lab 4 Radio Waves from the Galaxy Smiley Radio Telescope Lab 4 Radio Waves from the Galaxy Competency Goals This activity addresses the following competency goals Middle Grades 6 8: Grade 6 1.01 Identify and create questions and hypotheses

More information

CS488. Vision and Light. Luc RENAMBOT

CS488. Vision and Light. Luc RENAMBOT CS488 Vision and Light Luc RENAMBOT 1 Outline We talked about how to take 2D and 3D scenes and draw them on a 2D surface We will be discussing how to make these images more interesting Topics light, illumination,

More information

Photons: Light Waves Behaving as Particles

Photons: Light Waves Behaving as Particles Chapter 38 Photons: Light Waves Behaving as Particles PowerPoint Lectures for University Physics, Thirteenth Edition Hugh D. Young and Roger A. Freedman https://www.youtube.com/watch?v=ljtlrfkdg3a Poisson

More information

Light and Reflection Characteristics of Light. Electromagnetic Waves. Overview. The spectrum includes more than visible light.

Light and Reflection Characteristics of Light. Electromagnetic Waves. Overview. The spectrum includes more than visible light. Overview Light and Reflection 14-1 Characteristics of Light identifies the components of the electromagnetic spectrum, relates their frequency and wavelength to the speed of light, and introduces the relationship

More information

Quantum mechanics. At very small sizes the world is VERY different!

Quantum mechanics. At very small sizes the world is VERY different! HW8: Chap. 13 Concept 4, 8, 12, 14 (Due 11/3) Problems 2, 8 Quantum mechanics At very small sizes the world is VERY different! Energy not continuous, but can take on only particular discrete values. Light

More information

In studying the Milky Way, we have a classic problem of not being able to see the forest for the trees.

In studying the Milky Way, we have a classic problem of not being able to see the forest for the trees. In studying the Milky Way, we have a classic problem of not being able to see the forest for the trees. A panoramic painting of the Milky Way as seen from Earth, done by Knut Lundmark in the 1940 s. The

More information

The Tent We All Dwell In: Why the Sky is Blue

The Tent We All Dwell In: Why the Sky is Blue The Tent We All Dwell In: Why the Sky is Blue by Jeremy James "It is he that sitteth upon the circle of the earth, and the inhabitants thereof are as grasshoppers; that stretcheth out the heavens as a

More information

Chapter 3: Energy Balance and Temperature

Chapter 3: Energy Balance and Temperature Chapter 3: Energy Balance and Temperature Planet Energy Balance Greenhouse Effect Selective Absorption of Atmosphere Absorption, Reflection, Transmission Temperature Distribution Planetary Energy Balance

More information

Where Does Color Come From?

Where Does Color Come From? 8 Where Does Color Come From? INTRODUCTION In the fall, hundreds of thousands of tourists from all over the world go to New England to enjoy the changing colors of the leaves. Color is very important to

More information

Black Holes. When the body is outside of the gravitational pull, its kinetic energy and potential energy will be 0, so if we equate them

Black Holes. When the body is outside of the gravitational pull, its kinetic energy and potential energy will be 0, so if we equate them Black Holes What is a Black Hole A black hole is a point in space with so much gravity that not even light (the fastest thing around) can escape, hence the name. To an observer it would just appear as

More information

Inverse Square Law, Blackbody Radiation

Inverse Square Law, Blackbody Radiation Inverse Square aw, lackbody Radiation The Inverse Square aw for Radiation The amount of energy emitted in one second by a source of light is called its luminosity and is measured in watts. A source of

More information

Basic Properties of Stars

Basic Properties of Stars Basic Properties of Stars 1 Space is big. Really big. You just won t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it s a long way down the street to the chemist, but that

More information