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1answer
144 views

Reflection of a Plane Wave at Oblique Incidence

I am still trying to prepare for my electromagnetics preliminary exam, but I find myself stuck on understanding the origins of Eqs. 10.105a, 10.105b, 10.106a, and 10.106b on page 453 of Elements of ...
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2answers
2k views

reflection at speed of light when both mirror and viewer is travelling at the speed of light [duplicate]

consider me sitting on the top of a train which is travelling close to the speed of light, will I be able to see my image on a mirror which I'm holding in my hand??
2
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2answers
87 views

Art : A Particular Mirror

There is a particular mirror used here (1 minute 26 seconds) in this video, which reflects light in a way I've never seen. I was hoping maybe one of you might know what kind of mirror this is, so ...
0
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1answer
176 views

With a box that has perfect mirrors on the inside would it be possible to trap light? [duplicate]

With a box that has many perfect relective mirrors, would it be possible to trap a beam of light in the box indefinetly?
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1answer
382 views

Photo of reflection in magnifying mirror shows normal magnification. Why?

I just took a picture of myself in one of those magnifying shaving mirrors and in the photo I am unmagnified! Why is this?
1
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1answer
97 views

Reflection of a polarised beam

The past days I've been trying to understand how AutoFocus(AF) works on photographic cameras. There is a statement that says AF systems are polarisation sensitive. This means that they can only work ...
6
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1answer
188 views

Reflectivity of a glowing-hot metal surface

When a polished piece of metal (or steel in particular) is heated to incandescence, how do its reflective properties change? Given a mirror-like surface, would the object temporarily cease to act ...
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2answers
8k views

Does more reflective aluminum foil make a room cooler compared to less reflective foil?

Aluminum foil is said to be not absorbing light at all. It reflects light. So, does it mean that a more shiny aluminum foil will reflect more light and thus make the room more cooler as compared to ...
3
votes
1answer
925 views

What properties make a good barrier for microwave (oven) radiation?

Suppose I have plenty of food I want to heat (which will provide load) in the microwave, and one item I don't want to heat. What properties would make a material a a good shield, to reduce or prevent ...
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3answers
614 views

Light Ray Reflection from concave mirror

Suppose a ray of light hits a concave mirror and is parallel to the principal axis but far away from it such that it doesn't follow paraxial ray approximation. Will it pass through focus or between ...
0
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1answer
456 views

Confusing mirror problem

A piece of thin spherical shell that has a radius of curvature of 106 cm is silvered on both sides. The concave side of the piece forms a real image 79.5 cm from the mirror. The piece is then turned ...
0
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1answer
42 views

Can the choice of reflection angle for light can be derived from a minimality condition?

When the light hits on a surface, it reflects with the "same" angle as the one that hits the surface. I was wondering if this choice of angle can be explained by a minimality condition?
3
votes
1answer
376 views

Calculation the reflection coefficient of a mutlilayer material

For our project we have to study an infrared filter. This filter is composed of glass and several layers (nanolayers of titanium oxide, silver and cupper deposited on one side of the glass). Now we ...
3
votes
1answer
268 views

How to create visible reflections in shallow water?

Assumption: The only lights I have are candle, table lamp, and sunlight. What would I need to create visible reflection of an object in the shallow water contained in a 5 liter bucket? Is it even ...
3
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2answers
835 views

How does this trick with mirrors work?

Imagine two mirrors, set touching each other at right angles to one another. There is a 90 degree arc in which reflections can be seen, and a person standing in that arc can see himself reflected in ...
1
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1answer
146 views

Show that the plane of incidence is perpendicular to the surface of reflection

Is it possible to derive from the boundary conditions of the Maxwell equations for E and H, that the plane of incidence for an EM wave is perpendicular to the reflection surface? How? If not, what ...
2
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1answer
165 views

How much refraction occurs as a fraction of all reflection and refraction?

When light reaches a boundary between materials below the critical angle, some of it refracts and some of it reflects. For example, glass acts as a partial mirror with a dark background. Assuming ...
3
votes
2answers
207 views

why does a mirror show what is in front of it?

the only answer I can think of is that light is reflected from the objects in front of the mirror (visible color) and then reflects again off of the mirror to our eye, but im not quite satified with ...
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2answers
91 views

Hurdles in creating (close to) infinite images [duplicate]

Let's put an object (hypothetical superman) inside a "well sealed" box containing only mirrors. Is it possible to create number of images that will be close to infinity, assuming that resolution of ...
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1answer
80 views

choosing the right color

Context: My room is being painted, and i sit and study in a corner of the room, surrounded by walls on 2 sides, such that i am facing the wall. A tube light is at my 4-5 o'clock, and a ...
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1answer
189 views

Seeing a mirage through mirror?

Okay, I am not really good in physics (rather terrible), but nonetheless. So, I was just wondering if you can see a mirage, is there something special in our eyes that we can see it or what? I mean, ...
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2answers
889 views

All mirrors always shrink to 50% scale?

I have this geometric optics exercise here, in which a man is looking at himself in a mirror. Determine the minimum height at which the bottom of the mirror must be placed so the man can see his ...
2
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0answers
103 views

Bragg reflected electrons

Could you explain how does bragg reflection happen for electrons? What does it mean that when they satisfy Laue condition? This already is asked in Physics SE. They are Bragg reflected in the opposite ...
9
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1answer
7k views

Two mirrors facing each other

What happens when you place two mirrors facing each other? Is it possible to have an infinite amount of reflections?
0
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1answer
116 views

Ratio of distance between mirror and person

In perspective of a given example, if a man was to stand $2\ m$ away from a mirror which was $0.9\ m$ in height and was able to see his full reflection, what would the height of the mirror have to be ...
2
votes
1answer
637 views

How does light get into a stable optical cavity in the first place?

It is supposedly possible to trap a beam of light bouncing back and fourth between two mirrors in a stable configuration. As I understand it, this means the configuration will prevent further spread ...
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1answer
116 views

How reflected objects are composed and who is responsible for that?

Please refer to this image. The scene contains an object close to a mirror in the wall and a window, note that the reflected object is receiving more light than the object itself. I read some ...
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1answer
74 views

Reflected light from pulsars

If I point one telescope at a pulsar and record the image and then I point a second telescope at a mirror that has the image of the pulsar on it and record it, will the two recordings be different? ...
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0answers
350 views

Sum of intensity of reflected and transmitted waves

The given state: Let $\psi$ be a wave that passes from medium $a$ to medium $b$. Let $A$ be the amplitude of $\psi$. Let $R$ be the amplitude ratio of the reflected wave $\psi_r$ and the original one, ...
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5answers
1k views

Thought experiment regarding an object approaching a mirror

Here's a thought experiment I came up with in class today when my mind drifted (I however highly doubt I'm the first to think about this since it is pretty rudimentary) : Let's say superman ...
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0answers
32 views

Run with speed of light with a mirror in hand [duplicate]

Possible Duplicate: Reflection At Speed of Light Imagine you are able to run with the speed of light holding a mirror in your hand. Now will you be able to see yourself in the mirror?
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4answers
2k views

Does light accelerate or slow down during reflection?

After all, it does change direction when reflection occurs. So shouldn't it also accelerate? And since the acceleration cannot increase the speed of light, mustn't it slow down?
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1answer
2k views

How does the aluminium foil do the thermal and WiFi isolation?

Aluminium foil is widely used for thermal isolation. As far as I know it reflects the thermal infrared radiation. Also I've seen a lot of guides about strengthening WiFi signal by putting the ...
6
votes
1answer
259 views

How is it possible for an Ultrasound device to correctly interpret a negative density change in tissue?

I understand the principles of Ultrasound Imaging, and the mathematics behind sonar velocity, impedance, and reflection. I also understand that an Ultrasound device recieves an echo produced by ...
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2answers
722 views

Colors in the secondary rainbow reverse of that in the primary rainbow

Why the colors of Secondary rainbow is reverse of that in the color in the Primary rainbow? What can be the possible reason among the following options Because it is formed by one internal ...
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0answers
95 views

How does a lens affect the field of view in a mirror?

If one looks into a mirror, he can see a certain field of view. If he places a convex lens that magnifies (or a concave lens that does the opposite) in front of the mirror, but so that he can still ...
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1answer
997 views

Why does the spotlight reflected off of a rectangular mirror tend to become circular?

Background and setup When I was 12 I used to like a girl, we were almost neighbors and it was essential that our parents don't find out. So whenever one of us wanted to call the other they'd signal ...
2
votes
1answer
188 views

Can small clouds reflect enough light to hurt your eyes/blind you?

I looked out my window a minute ago and immediately noticed a very bright spot where a cloud and a jet/plane trail met. The spot was so bright that I thought the sun was behind it because it left that ...
0
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1answer
620 views

Refraction and Reflection Seismology

So I am wondering if I got the difference right. Both methods use explosives to send waves into the earth's surface. Now reflection seismology tries to get information from the reflected waves; the ...
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1answer
475 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 ...
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4answers
37k views

Why do diamonds shine?

I have always wondered why diamonds shine. Can anyone tell me why?
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2answers
363 views

A light and magnetic mirror paradox?

If light is an electromagnetic wave and lightspeed is constant (we ignore spacetime or gravity for this question) why can't we slow down light with a few dozen wellplaced magnets and electricly ...
1
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1answer
69 views

Rays in Symmetric Resonator

I'm having some trouble figuring out how to get started on this question: If I have a symmetric resonator with two concave mirrors of radii $R$ separated by a certain distance, after how many round ...
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0answers
44 views

Reflection of light [duplicate]

Possible Duplicate: What is the difference between a white object and a mirror? When I look at a red object under white light, I see it as red because it absorbs the other colours and ...
3
votes
1answer
477 views

Bragg condition for transmission: Why is the full diffracted angle Two times Theta? Or isn't it?

On a Bragg reflection with incomming angle Theta the total diffraction angle of the incomming wave is 2*Theta, of course. But I have Bragg transmission with electrons on a graphite crystal ...
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5answers
15k views

Free Optics Simulation Programs

I'm having an extremely difficult time finding an optics program that is easy to use and offers accurate physics simulations. I'm not asking for much, I just want to be able to simulate a laser going ...
3
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2answers
354 views

Redirecting light beams from beam splitters

I'm doing a project where I am taking a laser beam and sending it through a beam splitter. As I understand, approximately 50% of the light will go pass through and 50% will be reflected. So this means ...
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2answers
7k views

Refraction, reflection, and what is total reflection?

So if light travels from one media to another with a different refraction index, what may happen happen? Refraction, reflection or total reflection? I am quite confused as to the differences between ...
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votes
4answers
11k 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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3answers
4k views

Why does your reflection stay the same size when you move further away from the mirror?

This was an experiment I saw in my son's workbook. It said to mark out the top of your forehead and the bottom of your chin on a mirror using a whiteboard marker. Then slowly move backwards, and ...