All Questions
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Can anyone explain the relationship between the refractive index, the speed, wavelength and angle of a wave?
Can anyone explain the relationship between the refractive index, the speed, wavelength and angle of a wave?
in my book is states that $$n = \frac{v_1}{v_2} = \frac{\sin θ_1}{\sin θ_2} = \frac{λ_1}{...
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1
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Refraction of light with different wavelengths [closed]
A red light and blue light enter a rectangular glass block normal to its surface at the same time. Strictly speaking, after passing through the block, which pulse exits first?
Should I consider their ...
- 13
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1
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What is the definition of absolute refractive index of a medium?
I know the definition is the ratio of the speed of light in vacuum to the phase velocity of light in the given medium. Here, which color of light do we consider while calculating the ratio? For ...
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1
vote
2
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297
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Can X-rays travel quicker than visible light in a medium?
I have seen while reading a few books that the refractive index depends on lambda as follows by the Cauchy equation.
$${\displaystyle \eta(\lambda )=A+{\frac {B}{\lambda ^{2}}}}$$
From this, the book ...
15
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6
answers
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Why are red and blue light refracted differently if they travel at the same speed in the same medium?
When I look at Snell's law
$\frac{\sin\theta_2}{\sin\theta_1} = \frac{v_2}{v_1} = \frac{n_1}{n_2}$
I don't see any reference to wavelength.
If red and blue have the same speed in the same medium, why ...
0
votes
1
answer
171
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In what media the speed of light is slower than the speed of radio waves, if any?
In what media the speed of visible light is slower than the speed of radio waves, if any?
Particles can be faster than visible light, but other electromagnetic waves?
17
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5
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5k
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Do colors differ in terms of speed? [duplicate]
Here is a very simple question about light. As far as I remember from the school program, each color is merely one of the frequencies of light. I also remember that each color's wave length is ...
- 665
2
votes
1
answer
656
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Speed of light in different mediums with different frequencies
As I know the speed of the light doesn't change while it travels through a vacuum. But while it travels through a prism, it shows different deviation angles to different frequencies.
So ...
- 319
0
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1
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Speed of electromagnetic wave [closed]
On dispersion , speed of wave is inversely proportional to its wavelength . Therefore, gamma has max speed. But then in visible light , violet has least wavelength still it has least speed in visible ...
8
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2
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1k
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What really is the speed of light in a medium/vacuum, group or phase velocity?
While reading about refractive index 2 terms popped up, group velocity which alway slows down in a medium and phase velocity which may exceed speed of light. Say in a complete vacuum and using laser ...
- 13k
-4
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2
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390
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Speed of the color red
Taking aside all of the other variables that can alter the color's speed; i.e. sound, mass, water, magnetism. And just focusing on the color itself, how fast does the color red travel, using the means ...
1
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3
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4k
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Frequency dependence of the speed of light in air
According to this link, the speed of light of different colors in a medium should be different. But if the refractive index of light in air is 1 then this means that the speed of light in air and ...
- 1,116
5
votes
3
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3k
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Which electromagnetic radiation is faster in water, microwaves or light?
Well I've been asked this question, but I haven't been able to come with an answer yet using books and some web searches. The point is as the title says, to answer the question with the whole ...
Alan
2
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3
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4k
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Two different mediums can have equal index of refraction?
In other words: given a certain medium, is light's phase velocity unique?
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5
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1
answer
612
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Fermat principle: which index of refraction?
I am somewhat puzzled by a common formulation of the Fermat principle (light travel time), because it contains index of refraction related to phase velocity while light travel time through a slab of ...
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