Questions tagged [refraction]
Change in the direction of propagation of a wave when its transmitting medium changes. The tag does also apply to index of refraction.
1,624
questions
15
votes
3
answers
2k
views
Can the speed of light become complex inside a metamaterial?
The speed of light in a material is defined as $c = \frac{1}{\sqrt{\epsilon \mu}}$. There are metamaterials with negative permittivity $\epsilon < 0$ and permeability $\mu < 0$ at the same time. ...
- 9,910
15
votes
1
answer
10k
views
Why does the light at the bottom of the pool form this awesome pattern?
Take a look at the following picture:
Why does the light at the bottom of the water form this pattern? I have also seen the same phenomenon in all the swimming pools I've ever visited, of whatever ...
- 2,780
14
votes
3
answers
2k
views
Optics: Derivation of $\vec\nabla{n} = \frac{d(n\hat{u})}{ds}$
I have been given this formula from optics here, with no background:
$$\vec\nabla{n} = \frac{d(n\hat{u})}{ds}$$
Where $n$ is the refractive index and $\hat{u}$ is a unit vector tangent to the path $...
- 2,444
14
votes
3
answers
5k
views
Is it possible to calculate the distance to a rainbow by using the parallax method?
A colleague of mine (a physicist) recently claimed that it is possible to calculate the distance to a rainbow by applying the parallax method and that the result would be ~150 million kilometers, the ...
- 313
14
votes
2
answers
9k
views
Is there a theoretical maximum for refractive index?
May there be materials yet to be discovered which may have a higher refractive index than today's known materials (for wavelengths within the visible range)?
Is there a theoretical limit for the ...
- 367
13
votes
5
answers
62k
views
Does light change phase on refraction?
I have seen a lot about when light undergoes a phase change when it is reflected. But does it undergo a phase change when refracted and if so why and if not why not?
user43487
13
votes
3
answers
7k
views
Does light change color on its way through a window? [duplicate]
Looking at the refractive index of glass, it's around $1.6$.
Then the speed of light $x$ through light should be given by
$$ 1.6 = \frac{3.0\times10^8}{x}, $$
so $x$ is about $2\times10^8~\mathrm{m}~\...
- 1,432
13
votes
1
answer
26k
views
Why does the refractive index depend on wavelength? [duplicate]
Why do different wavelength get impeded more or less when in different materials? Moving with the same speed, but a longer physical distance would imply that the fields oscillate less times in the ...
user24082
13
votes
2
answers
642
views
Why does sunset spread over the horizon?
Why does sunset light spread horizontally over the horizon, instead of being radially spread around the solar disk?
I understand physics about refraction, and wavelength, and gradient difference ...
- 133
12
votes
3
answers
8k
views
Do photons actually slow down in a medium, or is the speed decrease just apparent? [duplicate]
Some places I've read flat out say light actually slows down in a medium, some say the speed decresae is just apparent but not real and that the photons still travel at the constant speed of light.
I'...
- 137
12
votes
3
answers
22k
views
Can a medium can have refractive index less than the reference refractive index (that is less than 1)?
I know taking the refractive index of the vacuum as unity, the refractive index of all the objects is calculated. So my question is that is it possible that a medium can have refractive index less ...
- 262
12
votes
4
answers
6k
views
Why does light not polarise off metallic surface?
I am aware that light partially polarizes upon reflection off a non-metallic surface, however, why is it that this only occurs for non-metallic surfaces?
- 1,720
12
votes
1
answer
9k
views
How does a one-sided glass work?
How does a one-sided glass work? If seen from the outer side, we can see through thinking it is transparent, while if seen from the inside, the glass acts as a mirror. How?
- 1,847
12
votes
3
answers
40k
views
Refractive Index of Air Depending on Temperature
How does the refractive index of air rely on the temperature? Is there a theoretical derivation of it?
- 2,125
12
votes
3
answers
11k
views
Is there any material which has same refractive index as the air?
If there is then what would happen if light passes through it?
- 147