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2

Just use snell's law, that is, $\mu \,\sin\theta$=constant, where $\mu$ denotes the refractive index and $\theta$ is the angle between the ray and the normal between a generic point and the point of incidence.The rest is math, you need to express $\sin\theta$ in terms of the slope at that point and solve the resulting differential equation.

0

The amplitude of the electric field in the medium depends on the medium's permittivity, which is not directly related to its density. Kinetic energy of the light wave decreases(velocity decreases as light travels from rarer to denser medium), hence the energy of the wave falls. This is not true -- the energy in an electromagnetic wave does not depend ...

-1

i think it's because of least time principle that states "light tends to travel a path in least time possible." as simple as that

3

First, The relative permittivity is dimensionless - not units of F/m. It is defined as the ratio of the permeability of the material to that of the vacuum. Second, by selecting a value of 4.7. you are defining the index of refraction to be $\sqrt{4.7}\approx{2.2}$. This is because for a dielectric such as glass, $\mu\approx\mu_0$ so ...

0

Your window is made of patterned glass, with regular changes in thickness. This is designed to diffuse light in order to prevent people outside from seeing what's inside (or you inside from seeing out; I don't know what your neighborhood is like). In your case, the patterns are extremely regular, so that each incoming beam of light will get spread into a ...

2

Please see http://www.ecse.rpi.edu/~schubert/Reprints/2007-Xi-JQ-et-al-%28Nature-Photonics%29-Thin-film-with-low-refractive-index-for-broadband-elimination-of-Fresnel-reflection.pdf (nature photonics VOL 1 MARCH 2007 p. 176 ) - pretty dense substance with a refractive index 1.05, close to that of air; low broadband reflection. Let me note that if you need a ...

6

The refractive index of a material differs from the vacuum because of interactions of the light with electrons in the material. So to a first approximation the refractive index is related to the electron density. Air has a low refractive index because it has a low density so it doesn't have many electrons per cubic metre. There are no solids or liquids with ...

0

A pentagon double prism in a globe shape format made from flat glass and silicone filled with water is a great way to disperse light into its different wavelengths. I have been told it is a great house fly deterrent as it confuses their many eye focal points, confuses them and makes them move on. would this be valid hypothesis or just an old wives tale?

1

What makes diamond so attractive (at least to some who have bought into the marketing craze created by the de Beers cartel) is not just the refractive index but the dispersion (aka "fire"), which is among the highest of all gemstones. It's also important to the quality of a diamond to be as translucent as possible, especially for the larger stones and the ...

3

The significance of $c$ is not the speed of light, it is the maximum speed a cause effect relationship can propagate. This comes to mean a speed that is observed to be the same by all inertial observers, as I explain in my answer here. It is experimentally found that the speed of light is equal to $c$, because the speed of light has this transformation ...

0

It is a said fact that the speed of light is insurmountable. But can the validity of this fact be questioned in another medium? Specifically, it is said that the signal front speed, $c_0$, is the upper limit of any speed value referring to the exchange of a signal; by definition and the meaning of "front" referring to the very first observation of any ...

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