All Questions
Tagged with optical-materials speed-of-light
7 questions
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How can the speed of light in matter be measured?
Experiments such as Focault's measure speed of light in matter. Focault's experimental set-up is based on the idea that it takes more time for light to travel through matter, which will result in the ...
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One-way speed of light and refractive index [closed]
It is recognized that special relativity does not require the speed of light to be isotropic, and having light propagate in each direction with the same speed is just a convenient postulate (see e.g. ...
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3
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Reason for change in colour of light
We all know that light has constant speed, and variable wavelength, and frequency. Suppose I have a big red glass square sheet. When white sun rays pass through it, their colour changes from white to ...
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Can light in a medium travel faster than speed of light $c$ in vacuum?
Refractive index of medium $m$, $n_m$, is given by $$n_m = \sqrt{\mu_r\epsilon_r}$$where $\mu_r$ and $\epsilon_r$ are permittivity and permeability of the medium respectively.
And, velocity of light ...
- 364
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Cooling photons to a solid state
Can we cool photons so the stop moving completely?
So they can behave like particles in a solid.
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1
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Are special relativity calcs affected by media?
Time dilation, increase in mass, Lorentz contraction calcs all involve velocity of light in vacuum. But in optical media light slows down. So what of relativity calcs in media? Do we ever need to ...
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Bandwidth-length product of an optical fiber
A multimode step index fiber has a numerical aperture of 0.2 and a core refractive index of 1.47 . Estimate the bandwidth-length product for the fiber assuming only intermodal dispersion when:
(a): ...
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