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4
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2answers
1k views

How do mirrors work?

Apparently, light is just a certain wavelength, or "the visible spectrum" of electromagnetic waves. If I recall correctly, my physics teacher explained to me that electromagnetic waves are basically ...
0
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2answers
324 views

How much of himself a person can see in the mirror? [closed]

A man who is $6$ ft tall is standing in front of a plane mirror that is $2$ ft in length. The mirror is placed lengthwise with its bottom edge $4$ ft above the floor on a wall that is $5$ ft ...
13
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4answers
8k views

Phase shift of 180 degrees on reflection from optically denser medium

Can anyone please provide an intuitive explanation of why phase shift of 180 degrees occurs in the Electric Field of a EM wave,when reflected from an optically denser medium? I tried searching for it ...
5
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2answers
3k views

Reflection of transverse and longitudinal waves

Why is it that when a transverse wave is reflected from a 'rigid' surface, it undergoes a phase change of $\pi$ radians, whereas when a longitudinal wave is reflected from a rigid surface, it does not ...
2
votes
1answer
225 views

Can Mirror box simulate long light travel?

Imagine that there is a cube box that has mirrors all 6 faces in . If we use a strong laser and enter in the box from a small hole on the box. The laser light travels in the box long time that we can ...
3
votes
2answers
362 views

At what angle does a single atom “reflect” a single photon?

Does this question make sense in the quantum world? Imagining a single photon (wave packet?) interacting with a single atom (its electrons etc) how do we currently describe/define the emitted photon ...
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0answers
172 views

How to derive a multi-reflection echo from a given single-reflection “trace”

Consider a one-dimensional semi-bounded "ray" (or thin "cylinder") of stratum (or just any homogeneous substance) which has several "features" along it's length (say, thin films). Consider a wave that ...
0
votes
2answers
706 views

Eliminating IR light reflection perceived by a steep viewing angle

I am having a problem with reflection on an acrylic surface, in the IR part of the spectrum. This reflection is interfering with an algorithm that looks at objects, as it makes two show up when only ...
1
vote
1answer
107 views

size and distance of mirror used in projected “smart” whiteboard

Apologies in advance for complete ignorance of optics (beyond conic sections) How is the size, distance, and angle of the mirror used here calculated? The mirror is I believe the open flap in front ...
12
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5answers
532 views

What longest time ever was achieved at holding light in a closed volume?

For what longest possible time it was possible to hold light in a closed volume with mirrored walls? I would be most interested for results with empty volume but results with solid-state volume may ...
42
votes
1answer
5k views

Why does a window become a mirror at night?

In day, when you look in the room through the window out, you can clearly see what happens outside. At night when it's dark outside but there's light inside you can look in the window but it becomes a ...
2
votes
3answers
586 views

Electromagnetic wave reflection vs. light reflection

Related: x-ray interaction with atmosphere I know that electromagnetic waves of particular frequencies reflect from the ionosphere. And the light (which from one perspective is an electromagnetic ...
0
votes
1answer
180 views

Reflectance of Round Moon vs Flat Moon

Treating the moon as an ideal, bright Lambertian reflector, I was trying to compare its efficiency as a light source to an equally-sized flat sheet of drywall. It's pretty straightforward to set the ...
0
votes
1answer
970 views

reflection, refraction and diffraction occur in radio waves, which one occurs the most?

One of the things about Radio waves is that they undergo different behaviors such as reflection, refraction and diffraction when in contact with obstacles such as walls, buildings etc. what i want to ...
12
votes
3answers
538 views

Is there a limit to the resolving power of a mirror telescope?

Like, if you flattened out Ceres to a 1 mm iron foil telescope mirror with 20x the surface area of the Sun, could you resolve details on the surface of an exoplanet? Could you make it arbitrarily ...
3
votes
2answers
580 views

What's it like in a sphere mirror? [duplicate]

Possible Duplicate: What happens to light in a perfect reflective sphere? I was working on my toy ray tracer when I pondered on this: Say we build a hollow sphere big enough to fit a ...
1
vote
2answers
1k views

How to calculate the temperature of a receiving point from concentrated solar power?

I'm exploring a DIY project about solar power and found very little resources that can explain in a not too simple but not too advanced way how to go about calculating important values in solar power, ...
3
votes
2answers
239 views

Light and parabola

I know that parallel light beams hitting a parabola will be focused at the focus of the parabola (f = 1/4a) and a light source at the focus of the parabola will ...
2
votes
4answers
3k views

Reflection At Speed of Light

I have looked online to no avail. There is two competing answers and I am curious to know which one is right. Someone asked me this question. If you are traveling at the speed of light can you see ...
2
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0answers
142 views

Modeling a spray painted polyurethane surface reflection

I'm modeling light interaction/reflection from a fiberglass surface with polyurethane epoxy (that is very reflective) that has been spray painted with a matte black paint. I'm looking for some input ...
3
votes
2answers
590 views

How to make mirrors give more authentic image of myself

My friend bought two normal mirrors from some shop probably IKEA, looking like this one: My images are different from the two. One is a little fatter and shorter, and the other a little thinner and ...
5
votes
2answers
666 views

Distance of objects in car mirrors

We've all seen that label on our passenger side mirrors that says, "Objects in mirror are closer than they appear." Why is this? Further, why does it only apply to the passenger side mirror, and not ...
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votes
1answer
653 views

Light Energy Absorption In Mirror

Let the amount of energy in one pulse of (laser) light be $E$, and the wavelength be $\lambda$. This pulse goes straight to the mirror, and it is reflected by the mirror. Let the reflectivity of ...
5
votes
3answers
1k views

What happens to light in a perfect reflective sphere?

Let's say you have the ability to shine some light into a perfectly round sphere and the sphere's interior surface was perfectly smooth and reflective and there was no way for the light to escape. If ...
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votes
6answers
2k views

How come an anti-reflective coating makes glass *more* transparent?

The book I'm reading about optics says that an anti-reflective film applied on glass* makes the glass more transparent, because the air→film and film→glass reflected waves (originated from a paraxial ...
5
votes
5answers
887 views

Why does light reflect more intensely when it hits a surface at a large angle?

I mean, what is happening at a microscopic level to cause this behavior? Here's what I got from Wikipedia: On Reflection (physics)#Reflection of light it says that "solving Maxwell's equations for a ...
-1
votes
1answer
173 views

How to apply Andreev reflection formalism to ferromagnet ,normal metal interface?

The traditional formalism for andreev reflection deals with what happens at normal metal, super conductor interface.http://en.wikipedia.org/wiki/Andreev_reflection (i.e when an electron from normal ...
2
votes
2answers
1k views

How do you calculate the intensity of light around the focal point from a focused collimated beam of light?

Problem/Purpose of me asking this question to you people who know more than me: So I'm doing a science project where I'm collimating a beam of light to a focus point in a light medium (water vapor or ...
6
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1answer
735 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 ...
4
votes
2answers
350 views

How long do reflections take?

How long does it take for a photon to be reflected? Starting with the photon being absorbed by some atom to the point it's reemitted? And what's the same point with pressure waves, like sound?
0
votes
1answer
475 views

How are these balls reflected after they hit each other? [duplicate]

Possible Duplicate: Physics of simple collisions I have 2 photos of the balls, one before the collision and one after the collision. They do a elastic collision. I want to know how is the ...
4
votes
5answers
1k views

Focusing Light with Flat Mirrors

What is the best way to focus (sun)light using flat mirrors? My goal is to start a fire. Cutting the mirrors is easy.
7
votes
2answers
3k views

How does reflection work?

In Newton's model of light as being composed of particles, it's easy to imagine reflection as being the rebounding of individual corpuscles off a surface. However, since light can also behave like a ...
4
votes
1answer
444 views

Why can't I see far when I look in a mirror?

I'm myopic. It's a fact. I understand exactly how it works because Internet told me light rays encounter themeselves too soon in my eyes... that is why I can't see far objects even if I see near ...
16
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4answers
2k 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 ...
2
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3answers
3k views

UV reflective surfaces

Do surfaces that reflect visible light efficiently also reflect UV light? If not, are there surfaces that do? (I have a large array of UV LEDs that I need to make larger and more diffuse, so I'm ...
4
votes
1answer
490 views

The Interactions of Light and Matter

So basically, I was trying to find a good answer to the question of how light interacts matter. Namely on the quantum level what causes matter to appear transparent, reflective, opaque, etc I came ...
4
votes
3answers
532 views

Virtual images in (plane) mirrors?

The following image is taken from teaching physics lecture Was man aus virtuellen Bildern lernen kann (in German): Now the cited paper claims that the left hand side is the correct picture to ...
5
votes
5answers
377 views

Trapping a lightray

Given a solid whose interior is a hollow sphere with perfectly reflecting mirrors. A small hole is drilled in the sphere and a photon is sent in at some angle. Will it always eventually exit through ...
167
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17answers
53k views

A mirror flips left and right, but not up and down

Why is it that when you look in the mirror left and right directions appear flipped, but not the up and down?
3
votes
1answer
1k views

Can you see yourself in a mirror when you are riding on top of a light stream?

What happens if you would ride on top of a light stream and you would look into a mirror that is in front of you, could you actually see your own face? I am asking this because I heard that nothing ...
1
vote
4answers
6k views

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 ...
1
vote
1answer
878 views

What determines how much light is reflected and refracted?

I'm currently working on a physics-based puzzle game with light refraction. I've read about the reflection/refraction incidence ratio, and how it's the proportion of the sine values of the angle of ...
2
votes
2answers
684 views

What type of electromagnetic wave can pass through silver or aluminium standard mirror?

I have been told (not sure if it is true), that mirror (and glass) do not allow to pass the electromagnetic signals of mobile signals. but for a standard mirror what type of wave can pass through ...
16
votes
2answers
3k views

How are classical optics phenomena explained in QED (Snell's law)?

How is the following classical optics phenomenon explained in quantum electrodynamics? Reflection and Refraction Are they simply due to photons being absorbed and re-emitted? How do we get to ...
2
votes
1answer
140 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 ...
24
votes
7answers
4k views

What is the difference between a white object and a mirror?

I was taught that something which reflects all the colors of light is white. The function of a mirror is the same, it also reflects all light. What's the difference? Update: But what if the white ...
14
votes
1answer
1k views

Why does my watch act like a mirror under water?

I have a digital watch, rated to go underwater to $100 \rm m$. When it is underwater it can be read normally, up until you reach a certain angle, then suddenly, it becomes almost like a mirror, ...
5
votes
3answers
2k views

How can I determine transmission/reflection coefficients for light?

When light rays reflect off a boundary between two materials with different indices of refraction, a lot of the sources I've seen (recently) don't discuss the relation between the amplitude (or ...