Change in the direction of propagation of a wave when its transmitting medium changes.

learn more… | top users | synonyms

1
vote
2answers
37 views

Refraction of light rays

My textbook says that the greater the refractive index of a medium, the lower the speed of a light ray passing through it. Seawater has a slightly larger refractive index than fresh water. Light ray ...
0
votes
2answers
16 views

Refraction of Sound Waves

When sound waves go from air to water what will happen to the wavelength and the angle of refraction? I used the approach that we apply to light waves and concluded the wavelength will decrease and ...
0
votes
1answer
30 views

How image is formed within the eye? [on hold]

So our eye has a layer of nerves. Our eye lens refracts and concentrates light rays of different amplitudes, and that concentrated impulse (of a mixed amplitude) induces a signal on some nerve; since ...
2
votes
0answers
45 views

Breakdown of Snell [on hold]

I have reason to believe that if we are using an accurately formed thin prism, then very near the working apex, where there are few atomic layers in a latticed prism, there will be inaccuracies in the ...
2
votes
2answers
33 views

How does change in medium affect object distance/image distance?

Say,we have a container filled with a liquid of refractive index $7/5$ upto a height up $H$. There exists a plane glass mirror at the bottom of the container. Now if a fish were placed at a height of ...
0
votes
1answer
116 views

Refractive index and color

Does the color of an object have anything to do with its refractive index, and if so, what is the relation? I tried googling this and searching through the questions on stack exchange, but I haven't ...
0
votes
2answers
171 views

Optical path difference

I have question about calculating optical path difference. $$\Delta L = \mathrm{(BC+CD)}\cdot n_2 - \textrm{BF}\cdot n_1$$ - why calculating path difference here we are subtracting $\mathrm{BF}$ ...
0
votes
0answers
25 views

How to solve the following wave equation? [closed]

We have paraxial beam propagating in a uniaxial anisotropic media. When such is the case wave can be divided into two orthogonal parts: Ordinary wave beam Extraordinary wave beam. The ordinary ...
14
votes
3answers
3k views

Is true black possible?

Black is the absence of light because it absorbs light, but when we create black paint or black objects, light is always reflected, either in all directions in matte or smoothly in shiny black ...
23
votes
1answer
832 views

How can my window not scramble the image of my yard?

How can an image pass through a window if the atoms in the glass randomly emit photons in any direction? I've read that glass is transparent because the atoms don't readily adsorb visible light, so it ...
1
vote
2answers
79 views

How come lenses alter the path of photons?

From what I know, photons are theorized particles and believed to be massless (just energy) and travel at the speed of light. How come a lens, which is an object made of atoms, can bend a light path? ...
3
votes
1answer
36 views

Does the angle of incidence change the refractive index?

I've been told if you plot a graph using the sine of the angle of incidence and the sine of the angle of transmission it should follow a linear regression $y = ax + b$. However, if you use certain ...
0
votes
1answer
24 views

Frequency dependence of electromagnetic reflection

I was surprised to see that the Fresnel equations for reflection depends on refractive index and angle of incidence, but they do not depend on frequency. Why is this case? Are they restricted to ...
2
votes
1answer
39 views

Does curving only the inner surface of a diving mask prevent blurred images?

Diving masks often have lenses built into the glass for divers who do not have perfect vision. The lenses in a diving mask faceplate often only have a curved surfaces on the inside glass. Why is this ...
6
votes
1answer
205 views

How would we see the earth if refraction of light was significantly stronger?

On worldbuilding.SE there is a question about the cosmological consequences of a world with super-high refraction and atmosphere opaqueness. I'm assuming the easiest way to minimally change the laws ...
21
votes
5answers
8k views

Eyes open under water

Yesterday I looked underwater with my eyes open (and no goggles) and I realized I can't see anything clearly. Everything looks very, very blurry. My guess is that the eye needs direct contact with air ...
45
votes
2answers
7k views

Why do I see better under water using swimming goggles? [duplicate]

I am myopic (I don't really know if this is relevant or not) and I usually swim without contact lenses. My vision is clearly better underwater when I am using swimming goggles. I have tried to ...
1
vote
2answers
250 views

Is light getting another color when travelling through a prism?

When white light travels through a prism the speed of this light is slowed down. Now there is a relation between speed of light, frequency and wavelength. So when a red light of 700nm enters a prism ...
1
vote
3answers
70 views

Derivation of the group velocity

I know that the group velocity of a light pulse is defined as $$\begin{split}v_g&=v_p\left(1+\frac{\lambda}{n}\frac{dn}{d\lambda}\right)\\ ...
-5
votes
1answer
88 views

Does this picture look wrong to anyone else? [closed]

There is a typo. One which obfuscates the main point and makes it difficult for anyone unfamiliar with the problem to deduce the answer.
0
votes
1answer
32 views

Sphere, silver reflector, refraction questions

A sphere with its back silvered can act as a retroreflector. When a fine beam of light is directed to the sphere as shown, it is refracted at the front surface, and focused on the rear interior ...
0
votes
1answer
235 views

Dispersion in a rectangular prism

Why are the colours visible only at the fringes of the light refracted through a rectangular prism?
0
votes
1answer
49 views

Can something go faster than the speed of light in a medium? [duplicate]

Since some mediums have an index of refraction more than 1, light goes slower than in a vacuum. Does this mean it is possible for particles to go faster than the speed of light in these mediums? If ...
2
votes
2answers
3k views

Radius of curvature and focal length

Is the radius of curvature of a convex or concave lens longer than the focal length of the lens? Does the center or curvature affect the focal point in a lens?
1
vote
1answer
33 views

Is Snell's law a product of Gravitational Time Dilation?

Due to the proximity of atomic structures in a solid liquid or gas, does the gravity of these atoms warp time enough to cause light to move slower from the perspective of an outside observer?
1
vote
1answer
60 views

Why is glass green?

When I look at a glass block at an angle the edges appear green, but when I look at the edge sideways, so that is directly in front of my eyes it appears transparent. Why?
8
votes
4answers
136 views

Why do the edges of glass blocks create a shadow?

I have always observed that the shadow of glass blocks becomes darker as the glass is moved away from the surface where the shadow falls. And I know this is because refracted light rays from the glass ...
14
votes
1answer
898 views

Why is everything not transparent? [duplicate]

There is a related question on this site here: Why glass is transparent? Which explains that glass is transparent because the atoms in glass have very large energy differences between energy levels ...
2
votes
1answer
73 views

When exactly do we substitute $\epsilon_0 \rightarrow \epsilon$ and $\mu_o \rightarrow \mu $?

If everything is embedded into vacuum, why aren't Maxwells Equations always with $\mu_o$ and $\epsilon_o$? When exactly do we have to make the substitution $\epsilon_0 \rightarrow \epsilon$ and ...
1
vote
1answer
195 views

Explanation for Refraction of light (change of angle) and Reflection

Refraction: I want a qualitative Quantum Mechanical explanation of why do we see light rays -in the classical picture- bend when light goes from one medium to another. I read that it is due to ...
0
votes
2answers
35 views

Difference between scattering and refraction?

I while back I learnt that when light is incident on a dipole the dipole will scatter the light, and when it is incident on a material of a different refractive index then the light refracts. From the ...
21
votes
3answers
5k views

How can muons travel faster than light through ice?

When a neutrino traveling through ice hits and interacts with an oxygen atom, muons are created. Cherenkov radiation can be created when muons travel through ice faster than light and create a ...
1
vote
1answer
30 views

Fresnel equations for perpendicular angle of entry [closed]

In many text books one finds for the fresnel coefficients for light perpendicular to the surface: $$r = \dfrac{n_1 - n_2}{n_1 + n_2}\quad\text{and} \quad t = \dfrac{2n_1}{n_1 + n_2}.$$ When I try to ...
0
votes
0answers
19 views

wave propagation modelling

what is the best modelling technique for modelling mm-wave propagation in electromagnetic environment. Right now,am working on how to use use Transmission-line matrix (TLM) and ray-tracing techniques
0
votes
0answers
16 views

Where can i find the complex index of refraction in the radio spectrum for aluminium?

I am looking for the (complex) index of refraction or the dispersion relation of aluminium for frequencies/wavelengths roughly between 30Mhz/10m and 30GHz/1cm. I have found a few sources that give ...
0
votes
1answer
74 views

Would forcing a photon to travel under $c$ even after it leaves a medium break Relativity? [duplicate]

So, I stumbled onto this article which really blew my mind (http://www.bbc.com/news/uk-scotland-glasgow-west-30944584). To sum it up, these researchers set up some kind of material that slowed a ...
5
votes
5answers
316 views

How is it possible for the wavelength of light to change in a medium?

So my physics class has just finished a long unit on optics while at the same time I've been trying to teach myself relativity. I admit my understanding is probably rudimentary, but I figured all the ...
1
vote
2answers
74 views

Why aren't clouds multi-colored?

Clouds are made out of tiny droplets of water. These droplets, to my understanding, act like tiny prisms (which is why there are rainbows after rain). From my line of thinking, if we had a room with ...
1
vote
1answer
24 views

What's wrong with finding the maximum refraction angle? [closed]

I am wrong with this derivation of $1 = \mu^2$ for arbitrary $\mu$ obviously, but I can't find what's wrong. $\delta := \theta_{1} - \theta_{2} $ where $\frac{\sin \theta_{1}}{\sin \theta_{2}} = ...
3
votes
3answers
998 views

Is there a way to increase the speed of light itself?

When light enters materials it slows down due to its refractive index (due to absorbing and re-emission of photons). But, is there a way to increase the speed of light itself? Can there be some ...
2
votes
2answers
119 views

How light splits up into different colours when passed through prism using QED?

I want to know how light gets splits up into different colours when it is passed through prism? How light interacts with atoms and electrons of the prism? Can someone explain this to me using Quantum ...
1
vote
1answer
33 views

Mirage formation in deserts [duplicate]

Why does a person sees water in the desert even then when no water is present there at that time? How does this happens?
0
votes
0answers
25 views

Refraction Explanation From Particle Perspective

I was wondering if there was an intuitive way of understanding refraction from a particle perspective. By this I mean, that before entering a lattice, a photon has some momementum, it then enters at ...
1
vote
4answers
4k views

Does light loses its energy when it passes through denser medium?

I know it does not because it emerges out of denser medium at 300,000 KM per second, but according to $E=mc^2$ and given that speed of light decreases inside denser medium with refractive index ...
0
votes
1answer
22 views

How lens for specs are manufactured for a given power? Do thickness, refractive index play role? [closed]

I read some where that if the prescribed glass power is more, glass must be made of higher refractive index to lessen the thickness. But from knowledge of physics, power just depends on focal ...
0
votes
2answers
54 views

Can a laser beam be captured in prism?

is there a way to shoot a laser at a prism (or something) and have it glow when the laser hits it? I want to make a small box with a small hole in it. With the prism in the box, when the laser is ...
2
votes
2answers
86 views

Why is this laser beam being scattered(and not)?

I was shining a laser beam through a liquid filled test tube(an ester particularly),and I found this phenomenon rather intriguing.Have a look. Now when I passed the laser straight through the ...
-2
votes
1answer
46 views

Calculating angle of refraction of water in this lab setup? [closed]

The setup of the experiment is as drawn in the picture (where the red circle is a rotating disk, the box is a laser and the straight line the laser beam and the semi circle in the middle of the ...
26
votes
3answers
148k views

Virtual vs Real image

I'm doing magnification and lens in class currently, and I really don't get why virtual and real images are called what they are. A virtual image occurs the object is less than the focal length of ...
1
vote
1answer
38 views

Deep confusion with conventions and signs in geometric optics

This is an equation given in my book. The question is why have they used a negative sign on the LHS? Now, if you try to derive the mirror equation with simple geometry, you get 1/v +1/u =1/f . ...