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There are three factors that need to be considered across all wavelengths: (1) the ability of the water droplet to refract and disperse the incoming light, (2) the ability of the eye to sense the wavelength, and (3) the ability of air to transmit it. The visible range we 'see' in a rainbow with our eyes satisfies all three. UV , depending on how short the ...

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engineer already answered it completely, I only want to add that the question is completely valid even if you already know that separation of wavelength occurs. The thing is, some materials are practically opaque or too much transparent (refractive index is equal to that of air and no separation occurs) in infrared and ultraviolet while transparent in the ...

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Is it possible that rainbows have ultraviolet bands and infra red bands and we are not able to see? Yes, see engineer's answer. As for whether we can see them, take a look at aphakia: "Aphakic people are reported to be able to see ultraviolet wavelengths (400–300 nm) that are normally excluded by the lens. They perceive this light as whitish blue or whitish ...

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Refraction of light in water droplets, leading to the formation of rainbows, is not limited to the visible range. Experimental evidence, compelling due to its simplicity, is shown in the following images taken by University of College London Earth Sciences professor Dominic Fortes. Check the alignment of the rainbow with respect to the trees in each of the ...

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I just made a complete answer for how rainbows are formed at What really makes a rainbow happen?. I'm answering here because the current answers say that it involves Total Internal Reflection, which is not true. There are internal reflections, but they are not total. And the light does not exist at just one angle, it covers a wide range of angles. Every ...

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1) Light from the sun strikes a spherical raindrop across half of its entire surface. So every angle of incidence A from 0 to 90 is represented. 2) Some of the light will reflect (uninteresting), but some will enter the drop. Its path bends due to refraction, entering the drop at an angle B (found by Snell's Law) that is always less than A. 3) The light ...

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The angle at which the light ray exits the material actually only depends on the index of refraction of the material at the last point at which it is in the material. You can demonstrate this if you consider a series of thin layers of materials (possibly all of which have different indexes of refraction), and when you perform the Snel's law calculation, ...

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The speed of light in a vacuum, or c, is 299,792,458 meters per second. Any other medium will slow light down. For example light takes about 40% more time to go through glass than vacuum. But media that would increase the velocity of light would violate fundamental laws of physics and can therefore not exist.

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The only thing I can think of being true black would probably be a black hole. As light does not bounce off a black hole.

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The problem with the suggestion of using polarization is that you now have the reflections off the polarizers to contend with. I think the short answer is "it depends on how 'black' you want it to be". "Truly black" = reflectance of 0. I am quite sure that is impossible - there will always be some probability of light scattering off a surface. All you can ...

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The main question I am getting at is, does time dilation have a refractive index? What I mean is, if I were to shoot a laser past a black hole, would the laser's path "bend" strictly from time dilation not considering the gravitational effects? We don't talk of gravitational lensing for nothing, but IMHO you're getting this back to front Joe. See what John ...

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Newcomers to relativity tend to regard concepts like time dilation and Lorentz contraction as somehow fundamental concepts from which relativity it derived, but this is not the case. Time dilation arises because the integral of proper time along the worldline of some object will not necessarily match the coordinate time measured by a distant observer. So to ...

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Yes. It is possible to produce rainbows of Ultraviolet or X-Rays in the lab. The SLAC team has already built a tool to produce rainbows of X-ray.

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Actually, the light beam does not follow the shortest path, but rather the faster path. Else the light would not bend but go straight there. This is Fermat’s principle. what point is the photon trying to reach? Good question. This point you are talking about, is in fact your eye. A straw in a glass of water visually bends at the interface. Look at ...

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It depends on how you define mass. I like to think of it as mass is just rest mass. I mean the mass you weight on a scale when nothing is moving. On different media light moves slower not because it gains mass but because of its interaction with the atoms in the media. The photons get absorbed and reemited in such a manner that when you sum the waves for ...

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First, we will look at the energy of a free relativistic particle of (rest) mass $m$ moving with velocity $v$: $$E = \frac{mc^2}{\sqrt{1-\frac{v^2}{c^2}}}$$ where $E=mc^2$ when $v=0$. We now consider a few cases: $m\ne0$: In this case, $E\rightarrow\infty$ as $v\rightarrow c$. Therefore, a massive particle that at any point of time is moving at less than ...

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Every particle needs to have energy to be a particle (if it had none it wouldn't even exist). Since energy is equivalent to mass and therefore gravitates I would say YES, all particles that have a speed less than the speed of light must also have mass. Because the speed of the particle is less than the speed of light an observer could travel with the same ...

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there are other parameters like the number of free electrons in the atoms of the material, atomic size etc. Close. While density of particles does matter, it also depends on the material property. More precisely, it is closely related to how the electrons react when situated under electromagnetic oscillation. Each bound electrons has its natural ...

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I want to know whether the amount of refraction of a given monochromatic light depends solely upon the density of the of the medium ( increase the density to increase the angle of refraction), or there are other parameters like the number of free electrons in the atoms of the material, atomic size etc There are a number of factors at play, the ...

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