Questions tagged [refraction]

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

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268 views

What will happen if the refractive index of lens is less than unity? [duplicate]

Generally the refractive index of any lens is greater than air. My question is what will happen if the refractive index of lens is less than unity?
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Gravitational refraction

I recently used another venue to ask about the speed of gravity, specifically if the speed of gravity is constant or if it is subject to refraction when passing through media, akin to light. The ...
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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 ...
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291 views

A Question About Brewster's Law

In most textbooks I read, they state that when the angle of reflection + angle of refraction = 90, there is maximum polarization. What I don't understand is what maximum polarization means. Does it ...
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Focal length of magnifying glass

Why a magnifying glass has a short focal length? According to its work the object must be between the focus and the optical centre, a large focal length will favour it, then why is it so?
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A Physics Problem Involving Refraction [closed]

I'm not sure how to solve this problem. I've considered using Malus' law, but then I don't know what theta is, preventing me from solving this problem.
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How can the refractive index be below 1 in a dielectric?

Upon checking the optical properties of different dielectrics, I found the interesting case of $Al_2O_3$. It seems to be reported with a refractive index below 1 in the infrared range of $10 - 12~\mu ...
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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 ...
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272 views

Spherical Refracting Surfaces

Why when given a question to find the image of a point object in a spherical refracting surface do you have to consider that there are two surfaces refracting the light? I assumed that one could ...
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At Home Experiment Shows Permanent Magnetic Field Does Not Refract

For an at home experiment I positioned a magnetic field so it would cross a boundary from air into water. I wanted to see if it would experience refraction similar to the refraction seen in ...
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4answers
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Refractive index of mirror

What is the refractive index of a common mirror (mercury coated)? As a mirror completely reflects the light ray, do it have infinite refractive index?
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Why would an object appear a different size when in water?

A friend of mine has a homework question and we're having some trouble figuring out what physical mechanisms come into play for this. An underwater swimmer sees a spherical air bubble that appears ...
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669 views

Why the water acts like a mirror from the air?

Why the ray of light what is in the air (n = 1) is reflected in the water (n = 1.33) surface, and acts like a mirror? The Snell law say what the ray is refracted deflected closer to the normal. Then ...
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Total internal reflection of sine wave vs smooth step function [closed]

If an electric field described by the function $$f(t)= \begin{cases} 0&\text{if}\ t<0\\ \sin(t)&\text{if}\ 0\leq t\leq \frac\pi2\\ \ 1&\text{if}\ t>\frac\pi2 \end{cases}$$ ...
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Why does purple appear in a rainbow?

It is said that people and digital cameras have color sense only for red, green and blue. So when we see violet/purple in a rainbow, whether with our eyes or in a photo, we should be seeing a color ...
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Why do the sides of my Fish Aquarium look like mirrors?

I bought a new fish aquarium which is square/cuboid in shape.My previous aquarium was spherical in shape. When I filled it with water and put the fish in two of them started acting very stressed so I ...
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The color purple in a rainbow

In a rainbow the colors order is red then orange (made from red and yellow, thus making sense that it appears in between them) the yellow followed by green after which comes blue (again green formed ...
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573 views

When does a monochromatic beam of light on a reflective surface get completely transmitted?

My book says when when a monochromatic beam of light is normally incident on reflective surface it gets completely transmitted. I am bit confused could you explain me?
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What is the upper bound for the index of refraction of space?

It seems that gravitational waves and gamma waves travail at about the same speed, arriving within seconds of each other over distances in the ranges of $10^6$LY. Naively, I would assume this caps the ...
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How do they derive the apparent-real depth formula?

We know that the refractive index of water to air is 4/3 . So, n=4/3 which should be n = 4/3 = n2/n1 , but my book says, 4/3= real depth/apparent depth. How have they put the “depths” in the ...
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Relativistic equations are medium dependent?

Einstein proposed that light travels with a universal velocity from Maxwell's equations on electromagnetism. But light has different velocity in different mediums, so does this imply that the ...
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Raise index of refraction of spherical lens

What happens to focal length and aperture of a spherical lens if you raise the index of refraction of the glass?
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58 views

Difficulty in understanding an optics question

So here's the question:- A thin film of transparent material of refractive index $1.52$ and thickness $0.42\ \rm \mu m$ forms a thin coating on glass of refractive index $1.60$. It is viewed by ...
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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/...
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If the velocity of light is different in different medium is it wavelength changes or frequency changes?

We know that the velocity of light is equal to the product of it's wavelength and frequency. And when light goes from vacuum to any other medium it's velocity changes depending the mediums refractive ...
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Titanium Dioxide refractive index

Titanium dioxide has high refractive index and it is one of the whitest materials. Does refractive index help in giving $\rm TiO_2$ white color? I know it appears white because it scatters all the ...
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Complex refractive index and absorption

I have a quite plain and simple question: Why is the imaginary part of the refractive index negative? I read it is to allow a positive sign in case of absorption. But how/why? I don't see why it ...
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Does total reflection occur when the wave is incident at a grazing incidence (angle of incidence equal to 90 degrees)?

I've posted the picture below from Introduction to Electrodynamics by Griffiths, 3rd edition. Is the phenomenon described talking about total internal reflection? Is it necessary for the incident ...
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Is light actually faster than what our present measurements tell us?

It is well established that the light speed in a perfect vacuum is roughly $3\times 10^8 \:\rm m/s$. But it is also known that outer space is not a perfect vacuum, but a hard vacuum. So, is the speed ...
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Why does reflectivity suddenly change around critical angle?

Why does reflectivity suddenly change around critical angle? For example, consider the situation when incident light travel in dielectrics A and go in to dielectric B. Assume the dielectric constant $...
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Refractive screen for myopia [closed]

Is it possible to create a screen for a computer monitor to allow a Myopic person to see the screen without glasses?
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Looking through a glass hemisphere [closed]

I've found the following question on IsaacPhysics.org . I've been working on it for a couple of hours but I cannot figure it out. A looking glass is used to read an ancient scroll. This lens has a ...
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2answers
175 views

Evanescent Wave Refraction

I recently learned that a beam of light that undergoes total internal reflection leads to the formation of an evanescent surface wave on the reflection surface. What happens if this wave encounters a ...
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Part of reflection/transmission of an impinging beam under 90°

I would like to know if there is something like a thumb of rule for a light beam impinging a surface under $90°$. In regards to Snelius there will be no refraction. But what about the amount of ...
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Working principle of an optical stretcher

I understand that while using an optical stretcher experimental apparatus we attach a small dielectric ball to the specimen of study which can either be a DNA molecule, a Biological cell or any ...
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Photon frequency when transitioning from one medium to another

$E=h\nu$ where $\nu$ is frequency and $h$ is Planck's constant. The frequency, wavelength and speed are related as $c=\lambda\nu$. When transitioning from one medium to another the speed decreases by ...
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What type of mirage is this?

I am very new to the world of mirages and would like some information as to the type of mirage in this picture which I took this morning. It is the cargo ship African Kalmia which passed my location ...
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278 views

Why does light bend towards the normal when passing through a denser medium?

When light passes from a medium with less refractive index to a medium with higher refractive index, it bends towards the normal. But why normal . Of course we can take an example of a car moving from ...
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Interference of 2 particular waves in Newton's rings experiment

The rings formed in this experiment are due to the interference of light reflected from the top and bottom surfaces of the thin film of air between the plano convex lens and the glass plate below it. ...
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Refraction of X-rays

According to Snell's Law, refraction occurs when an electromagnetic wave passes from one medium to another. My question is, how are x-ray images able to be produced if the x-rays refract as they pass ...
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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 ...
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Is the speed of light in the Universe always $c$?

Every one here knows that $c=(ε'×μ')^{-1/2}$. But what if ε' and μ' are different values in other parts of the visible universe. Maybe near the center of a Quasar galaxy or even a Neutron star?
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How does light actually interact with different materials? - PBR

I am a computer graphics guy in the area of physically based rendering and recently I've been searching on the net to figure out how physical is Physically Based Rendering (PBR). The nature of the ...
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659 views

What is bent light speed?

I have a question, if there is a straight beam of light that moves at the speed of light, is there a way to calculate the speed of bent light? since bending light causes it to lose momentum? Example, ...
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Literature on Reflection/Refraction of Waves

I completed the first year of my bachelor in Physics and astronomy in July. One of the courses was 'Waves and Optics' which we used the second half of Alonso & Finn's 'Fields and Waves' for. I ...
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What determines the property of vacuum that allows EM field to propagate?

As in case of sound it the disturbance that propagates by exchange of energy between particles. what is analogously related to em wave, where there is propagation of energy stored in electric and ...
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Arrow that changes direction home experiment

I saw this cool optical effect in a experiment on Youtube: https://www.youtube.com/watch?v=G303o8pJzls Could anyone explain to me why the arrow points in the opposite direction? I have read ...
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Is the reason the sunshine is 'extra bright' after rain due to refraction of the additional water in the air?

Quite frequently after the sun comes out after rain I experience a 30 minute period where the sunshine is 'unusually bright'. Such that it makes my eyes water. My question is: Is the reason the ...
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Is refractive index a property of the material or the light ray?

Why does it vary for e-ray and o-ray in nicol prism?
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Refraction and Internal Reflection

When a light is incident on the boundary of a medium with an angle greater than the respective critical angle, we obtain the angle of the refracted or reflected ray to be equal to the angle ...