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2

Yes it can be seen, rainbow can be considered as a set of points which form an angle of $42^{\circ}$ with the sun and our eyes, which comes out to be a perfect circle with center at our shadow made by the light coming from the sun. Usually we see a rainbow from ground and from there these set of points form a semicircle in the atmosphere. But if we observe ...


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You'll find a number of images on the internet such as the one below that claim to be a 360° rainbow. Most of these supposed rainbows are not rainbows. They are instead "glories" (wikipedia article). The image below is from that wikipedia article. Rainbows are much bigger than glories. A rainbow, like a glory, naturally is a 360° optical effect. You don't ...


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Take a hose that sprays water in fine droplets and direct it towards a bright object like the sun or a lamp... instant 360 degree rainbow!


2

For the conditions to see a part of a rainbow, I would say you need the following: sufficient moisture to form numerous micro spheres of water, which creates the refraction pattern the right angle between the observer and the sun sufficient mass-thickness with this angle and with this composition to build up a visible amount of color Since the sun is ...


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Its all upto the relative position of the observer and the sun. The imaginary line connecting the centre of the rainbow and eye of the observer called the line of vision makes the apparent struture of a rainbow. If the line of vision is a straight horizontal line with respect to the surface of the earth. You will definitely see a 360 degree rainbow. I ...


10

A classical explanation to supplement Rod's excellent quantum mechanical one: If you make a Huygens construction of wave propagation (I assume you know how to do that) then every point on the wave front is treated as the source of a new wave of the same frequency and phase. How that wave propagates depends on the medium it encounters. So the Huygens ...


41

When light is propagating in glass or other medium, it isn't really true, pure light. It is what (you'll learn about this later) we call a quantum superposition of excited matter states and pure photons, and the latter always move at the speed of light $c$. You can think, for a rough mind picture, of light propagating through a medium as somewhat like a ...


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An intuitive explanation could be that the photon has a longer road to be traveled in a medium?


1

Refractive index, as a number, actually varies with the frequency of the EM wave, so when someone quotes it as just some number (like: water's refractive index is n=1.33) usually it means in the optical frequency range ("for optical signals"). I suspect that is what's going on here. As to VF being greater than one or negative, I don't think I can explain ...


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Provided that the electron & the atomic beams also exhibit refraction,it seems that this is a particle's property.Deflection angle is proportional to particle's mass/size for specific medium.Photon behaves as particle in this effect.Mass is given by de Broglie equation:m=hv/c^2 , v=frequency


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Provided that the electron & the atomic beams also exhibit refraction,it seems that this is a particle's property.Velocity and deflection angle depends on particle's mass/size for specific medium.Photon behaves as particle in this effect.Mass is given by de Broglie equation:m=hv/c^2 , v=frequency


1

In optics, Fermat's principle or the principle of least time is the principle that the path taken between two points by a ray of light is the path that can be traversed in the least time. A more modern statement of the principle is that rays of light traverse the path of stationary optical length with respect to variations of the path. In other words, a ray ...


2

The key word here is continuity. The continuity boundary conditions for the electromagnetic field vectors sets these phenomenons. The tangential components of $\vec{E}$ and $\vec{H}$ must be continuous across an interface - the only way that they can not be is if there is a surface current flowing (which cannot happen in dielectrics). Likewise, the normal ...


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Whenever light (or any wave in general) goes from one medium to another, some of the energy of the wave is 'reflected' back through the first medium (at the same angle as the incident wave) and some of the energy (may be) refracted (bent) through the second medium. When light goes from a low refractive index medium to a high refractive index medium (such ...


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The phase change is what guides the process. 180 degrees phase change is reflection. Other phase changes are refraction.


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because in order for you to see, the light must reah your eyes. If the transmitted light was made totally parallel to the surface, then it will never reach your eyes. Thus, you will not see it.


3

It needn't. Take a look at Snell's law, $$n_1 sin{i}=n_2 sin{r}$$ If you're sending a ray from an optically denser medium to a less denser one, $n_1 > n_2$. As you increase $i$, for some value, $n_1 sin{i}=n_2$ (since the sine function gives values always lesser than $1$). For that value of $i$, you find that $sin{r}=1 \implies r={\pi \over 2}$, which ...



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