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Wavelength, speed and frequency of light: V=c/lambda, v being the frequency. Light emitted or radiated from a MONOCHROMATIC source has a range of wavelengths and velocity, the frequency is invariant, The speed of light actually is slowed down. That's why we define refractive index as c/v. Example: Light will travel in air having a refractive index 1.00029 ...


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Why do you say there is a phase shift at transmission into the first medium? You get a 180 degree shift at both the reflection on the front surface (air - coating) and on the second surface (coating - glass). You want these two reflections to be out of phase, so the round trip in the coating needs to be 180° also. That means total thickness of $\lambda / 4$ ...


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The classic example of when the correct path should maximize the time is inside of a mirrored ellipse. There are four possible paths for a light ray which begins and ends at the center (shown below). Two of those paths are maxima and two are minima. The fact that the original statement of Fermat's principle does not account for this is probably what Hecht ...


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By inspection, R approaches 0 as $n_2$ approaches 1. This should make sense intuitively, as 1 is the refractive index of a vacuum, which would not reflect light at all.


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Light frequency and wavelength are inversely proportional with a constant that is the speed of light (constant in vacuum). Both describe basically the same color within the spectrum, when light traverses a medium with a refractive index, its speed changes and affects the ratio of frequency to wavelength. What really matters is the energy carried by light as ...


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It seems your question comes down to "Why does light at least somewhat follow the curvature of the earth?". The answer is indeed refraction. Light has different speeds in different transparent substances, always slower than in vacuum. From this differing speed, you can show that a light beam is bent at the boundary between substances with different index ...


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Any energy principle is not being violated since the speed of the photon is never less than $c$ and hence the momentum is unchanging (in the classical sense). Why light travels slower than $c$ in a medium is because of the photons being absorbed and reradiated by atoms in the material. In a sense you can make the analogy of light traveling a longer path in ...


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Qualitatively, the thing that happens under water (when you wear a diving mask) looks like this: The green lines represent the path the light would have taken without the water, and therefore the "apparent size" of the bubble. But as you can see, the refraction of the light away from the normal (transitioning to a medium of lower refractive index) causes ...


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Use your power meter and graph paper to map out the reflectivity as a function of angle. The Fresnel equations (plots shown below) are rather sensitive to the relative indices of refraction of the glass-foil interface. If the index of refraction of the foil is higher than the glass then you will hit a plateau above the critical angle at which all of the ...


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I don't know the "official" answer but here is what I might try. I am hoping that others will contribute to make this a "good" answer. First - we were not told whether the wavelength of the laser is transmitted at all by the blue foil; but since blue foil typically absorbs red light, and most laser pointers are red (I have a blue one but they are ...


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Jon Custer hinted at something, which I think is best explained via an analogy. Imagine you can walk along a pavement at 4mph. When the pavement is empty, it takes you an hour to travel four miles. But when the pavement is crowded, you're dodging around people and bumping into them. You're still walking at 4mph, but it takes you an hour and a half to travel ...


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Feynman: The correct picture of an atom, which is given by the theory of wave mechanics, says that,so far as problems involving light are concerned, the electrons behave as though they were held by springs. So we shall suppose that the electrons have a linear restoring force which, together with their mass $m$, makes them behave like little oscillators, ...


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$c_0^2 = \frac{1}{ε_0μ_0}$ in vacuum. Permitivity and permeability (in materials) depend on frequency, in general. + In material you have $\epsilon=\epsilon_r \epsilon_0$, $v^2 = \frac{1}{εμ}$, where $v$ is a phase velocity of the light. - see http://en.wikipedia.org/wiki/Permittivity, where is a also a picture of frequency dependence of $\epsilon$.


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What you are seeing is stress in the window resulting in birefringence: the speed of propagation of polarized light depends on the direction of polarization. In the setup you have, the light in the sky is partially polarized because that's how Rayleigh scattering works; this partially polarized light is transmitted through the window where it rotates ...


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Is the speed of light affected by all mediums it travels in? Yes. Including space, but don't get distracted by virtual particles. The speed of light varies with gravitational potential. Search the Einstein digital papers on "speed of light" or "velocity of light" for examples like this: Also see Shapiro's 4th test of General Relativity along with The ...


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Metals refractive index is always complex number (and not only for metals). Imagine part shows the extinction coefficient $k$ - absorption in a material. Real and imagine part isn't connected. P.S. For engineering calculations real part sometimes is less than 1. Theoretically even for Fresnel reflection in dielectric we must use full formula with complex ...


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Imagine not the direction of the column but the direction of the front row. Suppose the front row of soldiers were carrying a horizontal bar, the one on the left hitting the swamp would slow down while the one on the right was still moving quickly so the bar (=wavefront) would change direction It's a slightly bad analogy. A much better one is: Imagine you ...


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Internal reflections from the facets of the object


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If the bottle and liquid are made of dielectric material, then the interfaces between different mediums reflect light, they don't absorb it (i.e. dissipate it as heat in the glass). This is probably a good approximation for your bottle. As a first approximation, once you have worked out your incidence angles with Snell's laww, you need to use the Fresnel ...


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Atmospheric refraction? "Atmospheric refraction is the deviation of light or other electromagnetic wave from a straight line as it passes through the atmosphere due to the variation in air density as a function of altitude. This refraction is due to the velocity of light through air decreasing (the index of refraction increases) with increased density." ...


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Index of refraction depends on frequency of the light. Indices can be very high in the far infrared. CO2 lasers operate at a wavelength of 10.6 um. This is about 20 times longer than visible light. The highest index I know of is GE, n = 4. See this for more. It is possible to "stop" light in a Pr-doped crystal. But this really sets the state of the crystal ...


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You can store light up to one minute so far. Basically you make a crystal transparent (low OD) at a predefined desired wavelength. When the light pulse goes in, you turn the crystal opaque (high OD). You retrieve the pulse by making it transparent again at the right time. The material is some Pr-doped crystal. For this purpose, it is hard to find a material ...



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