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

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7
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2answers
1k views

How can a slowed light ray bend?

If light is traveling through air, it slows down and ends up bending. But how? If I'm running straight, and I get slowed down, shouldn't I still be running straight?
1
vote
1answer
280 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
0answers
15 views

Can measuring the refraction index in an object measure the strength of the quantum gravity between atoms of the object? [duplicate]

Is measuring the refraction index of an object a way of measuring the strength of the gravitational force between the atoms of the object (measuring quantum gravity)? From reading Snell's law of ...
2
votes
0answers
67 views

Is Snell's Law valid even for on any curved surfaces?

Proof of Snell's Law can also done by using Fermat's principle of least time on plane surfaces. Can we prove the same result for any curved surfaces ?
0
votes
1answer
82 views

How is that possible, that n is inversely proportional to both $\lambda$ and $\lambda^2$ during refraction?

We know refractive index of any material $n = c/v$ where $c$ is speed of light and $v$ is velocity of light in medium. Therefore, $$n= \frac{c}{f\lambda}$$ where $f$ is frequency of light and $\lambda$...
0
votes
1answer
38 views

How long will the light exist inside the sphere?

Ok, so let's say we have a very thick, but hollow, metal sphere. The inside of the sphere has a radius of 100 meters. The sphere also has a door that can be opened and closed and when closed makes an ...
2
votes
2answers
631 views

Why is light energy 100% reflected in total internal reflection?

during reflection of light energy transfer is not 100%. when light from a rarer medium like air strikes a denser medium like glass slab, some part of light is reflected back and some of it is ...
1
vote
1answer
87 views

Refractive index of prism

The formula for the refractive index of a prism is: $$\mu = \frac{\sin (\frac{A + D_m}{2})}{\sin (A/2)}$$ However, this requires me to find out the angle of minimum deviation ($D_m$). This would ...
1
vote
3answers
1k views

Why does a ray passing through optical centre remain undeviated?

How can it be explained using the laws of refraction that a light through optical centre of a lens passes undeviated? If we assume the portion of the lens in the middle to be made of even number of ...
0
votes
1answer
171 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
1answer
49 views

Refraction under water

I have difficulties visualizing following task A diver is $d = 10 m$ below the water surface ($n_{water} = 1.33$). What is the diameter of the circle through which the diver can see the sky? ...
0
votes
1answer
75 views

Optics - how a lens distorts the image

If we consider a small object of length $b$ that is placed flat along the axis of a concave mirror, how will the image produced be different from the object? I know that a lens will magnify or ...
0
votes
0answers
15 views

What is A2L refractive index polynomial?

I'm working with a photonic modelling software and in the manual I saw that I can specify refractive index of modelled material with following polynomial: $n(\lambda)=c_0+c_1/(\lambda-\lambda_0)+c_2/(...
1
vote
2answers
33 views

Does the ray transfer matrix for a gap change, based on the index of refraction of the medium?

The ray transfer matrix for a gap is typically: $$\begin{bmatrix} 1 & d \\ 0 & 1\\ \end{bmatrix}$$ If I know that my glass is a thickness $L$ does the ray of light that goes into it travel a ...
1
vote
1answer
192 views

How to interpret the complex index of refraction?

The index of refraction which represents how much light gets refracted when entering a medium is defined as $$n = \frac{c}{v}$$ I have seen it stated in several places, such as here, that we can ...
0
votes
1answer
81 views

What is the physical explanation of Fresnel's equation?

When EM radiation is travelling between the media of different refractive indices, parts of it are reflected and transmitted according to Fresnel's equations. The amount of reflectivity and ...
0
votes
1answer
237 views

Angle of minimum deviation

A prism of angle $60^\circ$ deviates a ray of light through $40^\circ$ for two angles of incidence which differ by $11^\circ$. What is the refractive index of the glass of the prism? If we are given ...
2
votes
4answers
598 views

Why does light bend?

I have just read about dispersion of light by a prism and the thing which i donnot understand is that WHY does the light bend at all? Through prisms and slabs? I came to know that red light has the ...
0
votes
0answers
66 views

Proof of reflected and refracted waves being in the same plane as that of the incident wave and its projection on a planar interface

Please give a proof of reflected and refracted waves being in the same plane as that of the incident wave and its projection on an ideal planar interface between two linear, homogeneous, isotropic, ...
1
vote
1answer
195 views

Path of a light ray in a medium of varying refractive index [closed]

How do we get the equation for the path of a light ray in a medium of varying refractive index. I can draw a rough sketch, but don't know how do we get the exact curve. I encountered this while ...
0
votes
1answer
35 views

Refraction of light rays+ Energy

Does the amplitude of the light ray decrease when it moves from a rarer to a denser medium? I think that since Amplitude depends upon the Energy of the Light Ray, it should decrease. This is because ...
0
votes
1answer
51 views

Differences in speed of light calculations in glass

I wanted to determine the speed of light in glass by using both of the following formulas : $$v = \frac{1}{\sqrt{\mu \epsilon}} \simeq \frac{1}{\sqrt{\mu_0 \epsilon_r \epsilon_0}} \;\;\; \text{and} \;...
0
votes
1answer
116 views

Why light rays gets scattered when it enters a translucent window pane?

Consider the light source is the light post, outside the window of my house (Pic 1). When the rays from the light post enters through the window pane which is translucent gets scattered and forms a ...
3
votes
2answers
936 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?
1
vote
1answer
113 views

A material with very high refractive index

Suppose we have a material which has a very, very high refractive index, say 30-50. The critical angle for this material would be very small (1.5-2 degrees). Will the said object be even visible at ...
9
votes
3answers
228 views

Alongside a light ray (in another medium)

It is a said fact that the speed of light is insurmountable. But can the validity of this fact be questioned in another medium? If I pass a beam of light in, say water (here the light speed is ...
0
votes
3answers
168 views

Reflection during refraction

I have observed in a book that a light ray reflects during refraction, which is a partial reflection, but when does that occur? Is it related to the propagation of light from a greater to lesser ...
1
vote
1answer
77 views

Effect of the refractive index of a transparent layer coating a particle?

I am modelling a cell as a particle coated by a layer of a material whose refraction index might change. This layer is to resemble the membrane. The purpose of the model is to simulate what happens ...
2
votes
1answer
32 views

Absorption Magnification

I'm working on an optical project about the absorption of glass sheet and I need to measure the intensity of laser beam that has passed the glass sheet and compare that with the intensity of laser ...
0
votes
0answers
153 views

How to calculate the Refractive index of a glass sheet

My question is how to find the $n$ of a glass sheet with just aiming a laser beam to that. I've got lot of ways that let me find the $n$ ( Refractive index ) but I need the whole part of the ...
0
votes
1answer
894 views

Way of measuring thickness of a glass [closed]

Imagine you have a laser pointer and a glass. You don't know the refractive index of the glass and you just have Wavelength of laser! How can you measure the thickness of glass? (I have some idea but ...
40
votes
5answers
5k views

If a lens focuses all incoming light to a point, how do we get 2D images?

How do lenses produce 2-dimensional images, if a lens bends all incoming rays of light to intersect at the focal point? Shouldn't this produce a single dot of light on a screen placed at the focal ...
0
votes
0answers
34 views

Difference in Light's speed in various mediums [duplicate]

Light, despite not needing a medium and traveling due to oscillations of the electric and magnetic fields, slows down in mediums such as glass. I used to think it intuitively made sense, as we ...
2
votes
2answers
150 views

Why is rainbow always circular?

From the article that I read on physics classroom website on rainbow, rainbow is formed with red on the top and violet on the bottom because violet refracts more, and has a smaller angle of deviation ...
2
votes
1answer
190 views

Refraction of white light through a glass slab: what does it actually look like?

When a collimated beam of white light enters a rectangular prism, it develops slightly coloured edges due to the dispersive refraction of the glass: each ray in the beam is displaced differently ...
0
votes
1answer
77 views

Does the order in which light comes into a rectangular prism affect its dispersion?

I read about how when light comes out of a rectangular prism, there are violet and red fringes on either side of the light spectrum. The website didn't give the specifics in this subject, so I am not ...
2
votes
2answers
132 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 ...
0
votes
2answers
3k views

Why is the index of refraction different for different wavelengths? [duplicate]

The index of refraction can be written as $$n=\frac{\lambda_v}{\lambda_m}$$ where $\lambda_v$ is the wavelength in a vacuum and $\lambda_m$ is the wavelength in the medium. I’ve been told that since ...
0
votes
1answer
46 views

Can we measure the height of clouds using the sunset?

I was watching the sun set in San Francisco. As the Earth turns away from the Sun the tallest buildings remain lit longest. Light bending in the atmosphere allows this to last a bit longer. So, what ...
16
votes
1answer
1k views

Do neutrinos refract?

The most benign of interactions is refraction. While neutrinos rarely interact with matter in a sense like the photoelectric effect, does that mean that they don't refract either?
0
votes
1answer
119 views

How is light slowing down in a medium thought of in the photon picture? [duplicate]

The speed of light in any medium besides vacuum is smaller than $c$. In a classical way, I just look at that as a wave that propagates less fast, the change in EM-field is passed on slower. How should ...
3
votes
1answer
384 views

Why do we use the index of refraction for yellow light?

When we do problems with optics and refraction, we’re usually given a set of indices of refraction to work with; for example, the index of refraction in air is about 1.00, the index of refraction in ...
0
votes
0answers
134 views

How to actually determine the Index of Refraction of an object in different colors of light?

I would like some guidance as to how the IOR of an object is determined in different colored lights. Taking for example diamond, I know that the base IOR is 2.417, and the respective wavelengths of ...
3
votes
0answers
105 views

False sunset and false sunrise time estimation

False sunset and false sunrise are described . Here is a sample day rise and set time according to AccuWheather site and calculated value of sunrise and sunset in my country. Could you please help ...
0
votes
1answer
73 views

Is there a formula to calculate the deviated angle of a ray passing through a prism?

I'm assuming the angle of incidence to be the number of degrees from a perpendicular line on the side of a prism the ray starts passing through... I'm trying to figure out the angle the ray would be ...
3
votes
2answers
244 views

Using a transfer matrix to calculate beam width of off-axis Gaussian beam?

I have been reading a lot about ABCD matrices that are used for ray tracing. I can calculate the output offset $r_{o}$ (with respect to the optical axis) and the angle $\theta$ of the ray by $$ \...
1
vote
3answers
161 views

The speed of light/EM waves in vacuum; as if there was another one in non-vacuum?

Q1: is there a speed of a photon other than in "vacuum"? Q2: isn't "speed of light in vacuum" misleading? If I understand, that light moves with speed of light until there is "something in between" ...
0
votes
0answers
34 views

What are the physical optical limitations photonic metamaterials can offer?

Modern technology has introduced new photonic metamaterials that can extend optical properties beyond what standard materials can offer. For example a negative index of refraction is now possible ...
0
votes
1answer
577 views

Conditions for having refractive index less than unity?

Is it possible to have an index of refraction, $n < 1$, giving the "illusion" of a speed greater than $c$. As far as I understand it, is only the phase-velocity (which does not carry any ...
-1
votes
1answer
47 views

Why don't p-type seismic waves propagate along straight lines in the lower mantle?

Can you tell me why seismic waves (p-type shock wave) passing through the earth's lower mantle don't propagate along straight lines in particular?