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2answers
316 views

Refractive Index Base Wavelength

The refractive index of a medium is usually stated as a single "number" rather than something depending on wavelength. However, it does in fact depend on wavelength. This lead to a question I haven't ...
0
votes
2answers
100 views

What quantum mechanical effect allows light to gain it's speed when it moves from another medium back into air/vacuum? [duplicate]

According to refractive index's formula, we say that speed of light is other mediums is smaller than that of speed of light in air/vacuum. What quantum mechanical effects govern the increase in speed ...
1
vote
2answers
3k views

How is light able to form images? [duplicate]

Everyday we see ourselves in mirror and this is due to light which forms our image after reflection ( may be refraction sometimes) . But I wonder how can light carry the image. How is it possible that ...
0
votes
1answer
895 views

What causes refraction of light? [duplicate]

Time and again, I've been told that the change in the velocity of light makes it bend at the interface between two different media. But is there any explanation as to why that change occurs? Or is it ...
1
vote
1answer
161 views

Ray Optics: Reflection and Refraction

Suppose you have extremely sensitive photographic film and you can expose it in an optical system for a very long time. Will you be able to record a virtual image on film?
0
votes
1answer
766 views

Refraction of light In convex lenses [duplicate]

I came across this image when researching refraction in lenses. I can't understand why the light does not refract at the points which I have marked with burgundy arrows even though it is crossing a ...
3
votes
2answers
340 views

Why is a point source (star) more twinkling than a disc source (planet)?

Most scintillation effects are caused by anomalous refraction caused by small-scale fluctuations in air density usually related to temperature gradients. Stars twinkle because they are so far from ...
3
votes
3answers
796 views

Why does light travel slower in water relative to vacuum?

First of all read till the end. Do not mark as duplicate before finishing. The answer to the question above is that photons interact with molecules in the water which takes some time causing the net ...
2
votes
3answers
2k views

More light reflected off of double pane windows?

In glass windows, you get light passing through and light reflecting off the front and back surfaces. Would you get more light reflecting off of triple or double pane windows? Because you have double ...
1
vote
1answer
448 views

Properties of light and refractive index of materials

Why does the refractive index of a material dependent on the wavelenght of light incident on it.
0
votes
1answer
10k views

Why can't concave lenses be used as magnifying glasses?

I see why convex lenses work, but why can't concave lenses work? The light from an object diverges, making it wider, so technically that should make the object bigger, shouldn't it? Why isn't this the ...
0
votes
2answers
11k views

Why does light ray not change direction when it pass though the curve part of the semi-circular glass block?

Why does light ray not change direction when it pass through the semi circle part of the block but when it pass through the flat edge of the glass block it change direction.
3
votes
1answer
121 views

Pink on LCD screens, how is it possible? [closed]

On the LCD screens a flash makes 2 strips of color, 2 strips of white light, and a rainbow colored strip. This latest has weirdly a pink color in it. How is it possible? The pink color is not part of ...
1
vote
2answers
678 views

Double-slit experiment with two different mediums

How the interference pattern will look like in a double-slit experiment done with two different mediums? Air before the slit and glass after the slit.
0
votes
1answer
252 views

Is it possible to bend/refract light 180° using glass sheets of different refractive index?

If possible, How many combination between the numbers of the different layers and the thickness of each layer will give me 180° refraction.
1
vote
0answers
83 views

Which phenomenon does a normal window glass shows? [closed]

As we are able see outside from our window glass since it shows refraction in day but what happens in night as in night we are unable to see out since it shows reflection in night and sometimes it ...
3
votes
3answers
533 views

Order of colors after reflection in a raindrop

I studied two figures of sunlight reflecting in a raindrop: In the first image, red is shown above violet, but in the second image, red is below violet. Are both cases possible?
6
votes
2answers
167 views

Can you touch something which is massless?

Can one touch mass-less things? If not then why the light get scattered by the tiny particles present in air? If light is massless how can it hit particles or dust to get scattered? $$**OR**$$ ...
4
votes
5answers
2k views

Why is the speed of light said to be constant when we know it slows down in a medium? [duplicate]

If we ask someone what the speed of light is, they will say that it is constant and its value is $3\times 10^{8}\ \mathrm{m/s}$. But if we recall refraction of light, we say that when the light ...
3
votes
1answer
595 views

Some doubts related to interference of light by air wedge

We were taught "Interference by an Air Wedge" today in class. I have attached the image of diagram we were taught and the related formulae. However, I have still some lingering doubts about this topic....
1
vote
1answer
97 views

What is the phase velocity of light in graphene?

This article states that light can "slow down by a factor of a few hundred" when it strikes graphene. I've read elsewhere that the index of refraction of graphene is about 2.65 + 1.27i. According to ...
1
vote
0answers
50 views

Rainbows at the surface of calm cold water : mechanism?

Pictures Bigger versions : First | Second On this one we see the other side of the "main" arc and the white surface of water (see below). Observations So I observed these rainbows in a calm river. ...
3
votes
4answers
5k views

A lens inside a liquid is not visible. Why? [closed]

Are lenses inside liquid water invisible?
2
votes
1answer
362 views

How do EM Wave Boundary Conditions Comply with Conservation of Energy?

One of the boundary conditions of an EM wave crossing a boundary (dielectric materials, wave is TE polarized), where part of the wave is reflected and part is refracted, is $$E+E'=E''$$ where E is ...
0
votes
1answer
114 views

Does non-visible light also experience refraction?

Does non visible light such as x-rays or ultraviolet experience refraction and is their refraction index affected by their wavelengths (in their own spectrum)? Do they experience dispersion like ...
3
votes
2answers
4k views

Light refraction in a glass sphere: Is there a focus or not?

Recently, someone told me to pay attention when hanging a wind chime containing a glass sphere in front of the window, because a focus point might be formed on the curtains which might on a sunny day ...
-1
votes
2answers
89 views

Color of light after refraction

I know that the color of light depends on its wavelength. Also, when light moves from one medium to another, its wavelength changes. The question: So, when light moves from one medium to another does ...
-1
votes
1answer
425 views

Are images formed due to reflection or refraction and what do we see? HOW?

I am getting extremely confused about what we see as individuals : do we see reflected rays or refracted rays and what does our brain interpret? The concept has bewildered me for a long time. Googling ...
1
vote
2answers
6k views

Why don't light beams refract when they hit a curved surface [closed]

I saw a diagram that showed a light beam hitting a curved glass block (half circle) and nothing happened until it hit the flat surface, in which it refracted. Why doesn't it also refract when it hit ...
1
vote
1answer
2k views

Fish eye view problem

Why does the region outside the circular cone appears dark and the region inside the cone appears bright to a fish? I can't understand why as Im thinking that light rays from underwater objects are ...
19
votes
6answers
9k views

Are we seeing everything in a delayed manner?

If light is faster in vacuum medium than in air medium, does it mean that we are seeing everything in a delayed manner since we live in air medium? Is there any way to see things in actual speed i....
1
vote
2answers
699 views

Why do my friend's glasses make things look blurry when I put them on?

Yesterday I tried on my friend's glasses and noticed that they made everything look blurrier and farther away. If they do this to my vision, how can they make things look clearer and closer for him?
1
vote
2answers
268 views

Explanation of Reflection and Refraction

I've studied Huygens wave theory. But Huygens assumed that light is a wave in 'ether' which we know doesn't exist. Light is basically a electromagnetic wave. So I want to understand how light actually ...
-3
votes
1answer
122 views

Speed of the color red

Taking aside all of the other variables that can alter the color's speed; i.e. sound, mass, water, magnetism. And just focusing on the color itself, how fast does the color red travel, using the means ...
0
votes
2answers
984 views

Why is air transparent? [duplicate]

I made a rough calculation (probably having made a miscalculation though) following here and here to find out the number of air molecules in 1 cubic centimetre of air. The first website says there ...
4
votes
0answers
105 views

Would a Single Photon Refract? [duplicate]

I was trying to come up with the reason for why light refracts upon entering a new medium and after consulting with the internet I believe my theory is known as the marching soldiers analogy. This ...
2
votes
1answer
29 views

Boudary conditions for electromagnetical field

I have been studying the interface conditions for the vector fields $\vec{E}, \vec{D},\vec{B}$ and $\vec{H}$, and the following expression made me think a little: $$\epsilon_2 \vec{E_2}.\vec{n} + \...
5
votes
1answer
2k views

Why does the sky look darker blue directly above me, but get lighter in the distant sky?

it seems that the sky looks a bit darker right above me, but if I look into the distance, I see a paler blue.
3
votes
1answer
4k views

How does infrared light behave through water?

I have a project involving the detection of the presence of water in a cylindrical transparent plastic container (diameter=25cm) And I cannot put any device inside, so I was thinking of using and IR ...
-1
votes
1answer
88 views

Change in Speed of Light [duplicate]

Whenever light enters from air to glass its speed decreases but when it cross the glass and again come in air its speed increases. What is the reason behind this property? What is slowing it and what ...
2
votes
2answers
130 views

Why doesn't sunlight ALWAYS get split (into monochromatic) when going through the clouds?

It is my understanding that clouds are largely made up of water, which is known to split white light into its frequency components, and that's why we see rainbows sometimes. My question is, with ...
2
votes
1answer
971 views

Proving that angle of incidence over angle of reflection is constant in Snell's Law

First let me state what I think I know: Snell's Law states that $\frac{sin(i)}{sin(r)} = \frac{v_1}{v_2}= \frac{\lambda_1}{\lambda_2}= \frac{n_2}{n_1}$ where i is the angle of incidense and r is the ...
0
votes
2answers
95 views

Beam of light from glass to air

I am reviewing some concepts on light and came across a question that puzzled me. A beam of light is incident from a glass into air. The incident ray is 60 degrees to the normal. The question actually ...
1
vote
1answer
6k views

Calculating angle of min deviation of prism [closed]

Two rays incident with angle 40 and 60 on one face of equilateral triangular prism the angle of deviation are equal .find angle of minimum deviation?
-1
votes
1answer
53 views

Reflection and angle of refraction

Does the angle of refraction depend on the properties of the material if the angle of the incidence is the same for two different materials? Say I shed light on a surface with angle $ \theta $ and ...
0
votes
1answer
71 views

Refraction of light [duplicate]

In a prism, violet light undergoes more refraction than light of higher wavelength. Is there any explanation as to why light of higher frequencies refract more than light of lower frequencies?
1
vote
2answers
374 views

Refraction of light rays

My textbook says that the greater the refractive index of a medium, the lower the speed of a light ray passing through it. Seawater has a slightly larger refractive index than fresh water. Light ray ...
1
vote
2answers
2k views

Is light getting another color when travelling through a prism?

When white light travels through a prism the speed of this light is slowed down. Now there is a relation between speed of light, frequency and wavelength. So when a red light of 700nm enters a prism ...
0
votes
1answer
486 views

Sphere, silver reflector, refraction questions

A sphere with its back silvered can act as a retroreflector. When a fine beam of light is directed to the sphere as shown, it is refracted at the front surface, and focused on the rear interior ...
1
vote
1answer
3k views

Why is glass green? [duplicate]

When I look at a glass block at an angle the edges appear green, but when I look at the edge sideways, so that is directly in front of my eyes it appears transparent. Why?