Questions tagged [reflection]

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2answers
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Deriving the law of reflection for a moving mirror in relativity

I am following a training course and came across this proof, from my colleague, that the ordinary law of reflection $\theta_i = \theta_r$ does not hold in relativity: Let $S$ be a perfectly ...
5
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2answers
429 views

Is a Perfect/Lossless Mirror possible?

In traditional mirrors, some of the input light is absorbed by atoms in the mirrors surface and are 'lost' as heat, degrading the quality of the reflected image. Could this loss be compensated by an ...
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1answer
912 views

How can we explain, from quantum mechanics, why do we see light rays bend when light goes from one medium to another? [duplicate]

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 ...
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2answers
3k views

What is this blue thing in a photograph of a bright light?

It looks like the bulb of the lamp beside it but how why what
9
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1answer
296 views

Can gravitational waves resonate?

Can gravitational waves resonate? - Perhaps by creating standing wave interference in a cavity? Could that feasibly happen either in nature or by engineering?
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4answers
630 views

How can reflection and refraction be explained classically and microscopically?

I was trying to explain something about Brewster's angle and realized I don't completely understand how reflection and refraction work on the microscopic, classical level. Consider a plane polarized ...
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1answer
2k views

Polarization and mirrors

When a light beam reaches a dielectric surface, the incident and reflected beams have different intensities depending on polarization. For the so-called Brewster's angle, the reflected light is ...
6
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1answer
996 views

What is happening at a atomic level when light hits an object?

I just began learning light and optics and I am just so confused about what reflection, refraction and absorption is. I think a large part of my confusion stems from exactly what happens at an ...
5
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1answer
2k views

What causes these rainbow effects using a polarizing filter on an airplane?

I know that light reflected from a surface at 45° is polarized and that for a similar reason skylight arriving from a direction orthogonal to the sun is polarized too. Photographers make use of this ...
5
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4answers
6k views

During reflection does the emitted photon have same properties?

When light (photon) is reflected the the original photon is absorbed by an electron and then emitted again. Does this "new" photon have the same wavelength, frequency etc. as the original?
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2answers
969 views

Does Snell's law still apply after total internal reflection has occurred?

Snell's law states that: \begin{align} n_1\sin\theta_1 &= n_2\sin\theta_2\, ,\\ \sin\theta_1 &= \frac{n_2}{n_1}\sin\theta_2\, ,\\ \sin\theta_1&\propto \sin\theta_2\, . \end{align} The ...
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2answers
751 views

Light-matter interaction and an object's appearance

I am taking a course in Computer Graphics, and the teacher said we could put materials in there main categories: mirror like glossy or specular diffuse He suggested that the law of reflection is ...
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1answer
2k views

What range of light wavelengths can a typical mirror reflect?

A typical mirror is capable of reflecting the full spectrum of visible light. Can it also reflect other wavelengths both longer and shorter? What is the range?
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4answers
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How does the moon reflect light?

We can see the moon in the night because it reflects sunlight. But the light is incident on the opposite side of moon with respect to the observer in the night. In this case, how does the moon ...
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3answers
7k views

Is there 100% reflective mirror…i just want one

I have heard there are none right now...but i saw something that said something about 100% reflection. Forgotten completely. sorry. I want it, i think it'd be very amazing to save sunlight in it from ...
12
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3answers
18k views

What is the color of a mirror?

A mirror couldn't be white, as then you wouldn't be able to see your reflection so clearly. It wouldn't be transparent, as that then won't reflect. So what color is it?
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1answer
250 views

Does total internal reflection really reflect every single photon?

In certain cases of refraction, light can be totally internally reflected (TIR) instead of being transmitted. One learns that literally 100% of the light is reflected back in such an interaction. My ...
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3answers
1k views

How to arrange mirrors so I can't see myself?

If I wanted to surround myself with mirrors how would I need to arrange them so that if I stood in the middle of them I couldn't see myself in any reflection? For simplicity let's just say we only ...
6
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3answers
6k views

How would an X-ray mirror work?

I was wondering if light can be reflected how can someone reflect X-ray of what material does it need to be made of and is its design completely different to that of our original mirrors? Does this ...
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2answers
4k views

Difference between Scattering and Fluorescence

It is often said that substances, objects have color because they selectively absorb all color of sunlight except one. The wavelength that is not absorbed reaches our eyes and we perceive it as "color"...
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1answer
1k views

Special Relativity & Mirror Reflection

If you move at $5$ $ms^-$$^1$ towards a plane mirror, your reflection moves $10$ $ms^-$$^1$ towards you. But what happens if you're moving much faster, say $0.8c$? Would your reflection move at $1....
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1answer
200 views

Explanation for possible interference on a home mirror?

I've noticed that a few peculiar things about home commercial mirrors that aren't present with industrial/scientific mirrors. This is one of the mirrors I used. With the mirror like the one above, ...
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3answers
759 views

Why white flat surfaces are white and not mirror-like reflective?

White color means very little optical absorption, so why a white flat surface (such as a wall) appears as white and not as a mirror-like surface?
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1answer
99 views

Why certain objects reflect while some refract?

Both reflection and refraction are processes where absorption and re-emission of electromagnetic waves occur, but they differ in the direction of re-emission. What factor particularly decides the ...
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2answers
2k views

Why can't we reach the ends of rainbow?

Rainbows are spectacular things. But I imagine why we can't reach to the ends of rainbows. Do rainbows have no ends ? If so, why can't we reach at them? If you go closer,they will go further. Why?
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2answers
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Does the law of reflection hold for balls bouncing inelastically on inclined planes?

There is a 2-part problem in my physics book in which part I gives some information about a ball being dropped vertically onto a flat surface, and we are asked to deduce the coefficient of restution $...
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1answer
959 views

How does QED explain reflection? [duplicate]

By reflection of photons from a mirror, the mirror must get an impulse of 2p=h/pi.l for every photon. This means that the mirror receives kinetic energy. But the photon has the energy it has before ...
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2answers
54 views

Why do only tangential branches reflect?

In this picture note that only the branches tangent to the light are lit up, so concentric circles of lit branches appear around the light: I've noticed I similar effect with the peaks of water waves ...
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4answers
2k views

Double rainbows

In my garden, when I'm watering the plants I sometimes see a rainbow or two. How did two rainbows appear? Why can't I see three rainbows then, or how can I see three rainbows?
2
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2answers
523 views

Can we have light through out the house with out light being switched on for all the time?

Optical fibres are used to transmit light from one place to the other along curved path in a more effective manner. The optical fibres consist of thousands of strands of a very fine quality glass or ...
2
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1answer
312 views

Reflected and refracted wave sphased

When we derive refraction and reflection laws for a generical plane wave on a surface, we say that reflected and refracted must be in phase with the incident wave. Why a medium cannot do a sphased ...
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2answers
3k views

Can matter have 100% reflection?

Is it possible to have matter that reflects all the light and does not absorb light at all? If thats possible then we can store light inside it right? I think we can trap light inside that matter in ...
2
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1answer
320 views

Can electrons within a positive ion absorb and reflect light?

I understand that in a crystalline metallic structure, such as one making up a bar of gold, there are one, or more, valance electrons of each atom that have left their outer shell (became free ...
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1answer
2k views

Why is a rainbow curved in shape?

Why is a rainbow curved in shape? When dispersion of light takes place, light splits into seven colors, but when rainbow is formed it appear to be bent. Why does this happen even though light travels ...
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2answers
536 views

What is the cause of reflection?

A wave that meets the boundary of two substances with different propagating velocities is partially reflected. Does anybody know the reason behind reflection?
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1answer
672 views

Question on real image formation by light

Before starting a detailed tour of physics, I wanted to clear some of my basic doubts. I have studied the image formation by mirrors and lenses and I'm aware that a real image is formed of an object ...
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3answers
62 views

Reason for black and white colour

We always say that an object is black to a person's eyes if it absorbs all incident light or doesn't reflect anything, and white if it doesn't absorb and reflects all. My question is which specific ...
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1answer
54 views

Acoustic amplitude transmission through multi layer medium

I have an acoustic wave with amplitude $A$ in ice. It passes a water-filled crevasse, and I want to calculate the impact of this passage on the magnitude of the amplitude (I do not care for the phase)...
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2answers
160 views

In diffraction When wavelength is less than slit width then does the scattered light gets absorbed & emitted from the wall or just rebound?

I know that when the slit width is less than that of wavelength then the slit will act as a point source and scatter the light in all directions. But my question is that during the scattering of ...
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1answer
1k views

A mirror room with light inside theory [duplicate]

Let's say there is a room that has the shape of a cube with all the walls, roof and ground made of mirrors, it is all mirrors and theoretically we managed to have light in there without a source. (...
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0answers
140 views

Why is a $\pi$ phase added on reflection and why do things change with absorption? [duplicate]

Mathematically, how does a $\pi$ phase shift appear upon reflection of light off a optically denser medium? Why is it always $\pi$? If the medium is absorptive it is no longer $\pi$?
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2answers
229 views

Phase change on reflection only 0 and $\pi$ allowed

We know that when a wave on a string is reflected from a hard boundary, the phase change is $\pi$, and from a soft boundary, the change is 0. My question is: this two conditions (hard and soft ...
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2answers
2k views

How can opaque black object occur?

I know the fact that a material appeared as black when all wavelength photons were absorbed. I also know that opaque object is the result of reflection and scattering of light wave. Is it right? ...
0
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1answer
168 views

Destructive interference and energy conservation

In case of interference,we know,energy is neither destroyed,nor created; but only redistributed.But in the case of an extremely thin film,due to a reflection and hence a phase difference of pi, the ...
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4answers
7k views

Why can't my eye see itself in the mirror through polarizing 3D-glasses?

I found a pair of polarizing "3D glasses" lying around, and tried to look at myself in the mirror while wearing them. To my utter confusion, when closing the left eye and only looking through the ...
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1answer
947 views

Reflection of light rays

A set of light rays emitted from a point of an orange hits a smooth and flat surface. My question is: The angles of incidence are different, light rays are reflected towards different directions, why ...
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4answers
17k views

Why does water reflect light?

Why does water reflect light? What is actually happening when light is reflected by water? We know why metals reflect light; water, however, is not metal, but it still reflects light and we can see ...
4
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1answer
115 views

What is the minimum number of metal atoms necessary to make a mirror?

I am still unsatisfied with what I have read so far about the physical basis of metallic mirrors reflectivity. In particular, I am skeptical about the idea that individual electrons serve as mirrors ...
4
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1answer
393 views

How does light pass through rough glass?

Light incident on a rough surface will be diffuse after passing it. Angular intensity depends on the grinding of the glass surface. I'm trying to find information about the scattering indicatrix of ...
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2answers
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Why does a negative reflection coefficient correspond to a phase difference of $\pi$?

As an example I will use the Fresnel equations: $$t_{p,s}=\frac{2\cos\theta^i}{\cos\theta^{t,i}+\frac{n_2}{n_1}\cos\theta^{i,t}}\tag{T}$$ $$r_{p,s}=\frac{\cos\theta^{t,i}-\frac{n_2}{n_1}\cos\theta^{i,...