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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 ...
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1answer
262 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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2answers
481 views

Light Ray Reflection from concave mirror

Suppose a ray of light hits a concave mirror and is parallel to principle axis but far away from it such that it doesn't follow paraxial ray approximation. Will it pass through focus or between focus ...
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1answer
272 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 ...
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1answer
37 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?
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1answer
191 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 ...
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1answer
190 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 ...
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2answers
424 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 ...
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1answer
113 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 ...
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1answer
101 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 ...
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2answers
135 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
71 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
73 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
143 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
320 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 ...
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0answers
66 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 ...
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1answer
2k 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?
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1answer
86 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 ...
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1answer
349 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
96 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
68 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
196 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, ...
14
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4answers
661 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
29 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
870 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
1k 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 ...
5
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1answer
172 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
240 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
62 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 ...
14
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1answer
450 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
126 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 ...
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1answer
261 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
270 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
21k views

Why do diamonds shine?

I have always wondered why diamonds shine. Can anyone tell me why?
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2answers
255 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 ...
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1answer
60 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
37 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
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1answer
335 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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4answers
7k 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 ...
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2answers
242 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
3k 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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3answers
6k 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
2k 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 ...
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1answer
2k views

Why does your reflection suddenly turn upside down while slowly walking away from a curved mirror?

Many people should have realised, when looking into a concave curved mirror (or even a rather reflective spoon in that fact) at a close distance, you will see a slightly distorted reflection. But as ...
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2answers
191 views

How can one prove that the number of images formed by the reflecting surfaces of two plane mirrors at right angles to each other is 3?

How can one prove that the number of images formed by two plane mirrors at right angles to each other is 3? Is there a mathematical proof for the same ?
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4answers
2k views

What happens when a photon hits a mirror?

When a photon of light hits a mirror does the exact same photon of light bounce back or is it absorbed then one with the same properties emitted? If the same one is bounced back does it's velocity ...
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3answers
1k views

Reflection of Electromagnetic Waves

Visible light - Being an Electromagnetic wave is reflected by glass (take mirror). Would all other waves in the electromagnetic spectrum be reflected in the same way by our simple mirror... For highly ...
5
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1answer
961 views

What IS reflection?

How does quantum electrodynamics actually explain HOW reflection occurs on a microscopic scale? Note that Feynman's QED lecture series/book is not sufficient, as he only assumes that light DOES ...
2
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1answer
782 views

What are the properties of the partially polarized light on refraction?

When a ray of ordinary light is passed on the surface of the water the reflected light will be completely polarized( vibrations in one plane). My question is what will be plane of vibration in the ...
2
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2answers
745 views

Rotating mirror - Foucault's measurement of light speed

Some time ago I came across a secondary web source on measurement of light speed in water made by Foucault around 1850. I append its redrawn scheme below (light is reflected from the rotating mirror ...