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I polarize the slits (one H, the other V) of a Young's double-slit. If my source is H or V, do I see fringes? What about if my source is D or AD?

It looks like you've got some good answers here. For even more fun try this experiment with mutually orthogonal circularly polarized light through each slit. For example, left hand circularly ...
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What will happen if the inner walls of the perfect blackbody(shown in the image) is made perfectly reflecting?

Q1: If light can come in through the opening, it can also come out through it. So it isn't possible to concentrate energy inside arbitrarily. Reflecting walls means the outgoing radiation spectrum ...
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What is the "Doppler mismatch"?

This question had puzzled me for hours too. Actually, I am reading this paper right now. I used to think that EIT peak locates at the two photon resonance($\Delta_p+\Delta_c=0$, where $\Delta_p,\ \...
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What exactly is "dense" in Optical Density?

Devil's Advocate Answer. Optical density is the property of a material that affects the speed of light in that material (higher density, slower light speed) and the index of refraction is a measure of ...
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Can X-rays travel quicker than visible light in a medium?

Cauchy' dispersion relation is a simple model devised for visible light in very weakly absorbing media. Coefficients $A,B,C$ can be determined by fitting the experimental results. It is not applicable ...
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What exactly is "dense" in Optical Density?

In this particular context, "optical density" refers to the index of refraction of the material. This is not a common usage for physicists, as can be seen from the comments below. So, beware ...
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1 vote

Tangential rainbows?

It is kind of hard to tell what is what from the photos - I'm sure it was stunning in person though. I reckon what you're seeing is a form of halo though - an optical phenomenon produced as light ...
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What is the clear difference between interference and diffraction?

Although diffraction and interference are mostly referred to phenomena of light, I would like to start with water waves. The problem is best observed at the surface between water and air. In a water ...
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How to understand the polarization rotator using a PBS, a quarter-wave plate, and a mirror?

The problem is that you need to be careful with the fast axis of the quarter wave plate (QWP). Here is how your example works, using the same optical calculus software as I used in another answer here....
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How to understand the polarization rotator using a PBS, a quarter-wave plate, and a mirror?

Your error is the reasoning with the flipping of the handness in the mirror. The handness may look like it was flipped, but the direction of the beam flipped also, meaning that the handness (which is ...
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What is the significance of back focal length in a lens?

Never mind, found the answer on photography stack exchange: https://photo.stackexchange.com/questions/61728/what-is-the-importance-of-the-back-focal-length-of-a-lens Basically, it's just a mechanical ...
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3 votes

Units make speed of light dimensionless..?

It's a bit ill-posed but this is defining natural units (maybe look it up on wikipedia for more info), we just set the unit of speed as c (speed of light), so as the speed is unit 1 it means that ($[]$...
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How does a rainbow show all of its colours?

The diagram produced in the question has a couple of errors and almost answers the question. To a very good approximation the rays coming from the Sun are approximately parallel and the reflection ...
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What is the clear difference between interference and diffraction?

From Wikipedia article on Diffraction: Diffraction refers to various phenomena that occur when a wave encounters an obstacle or opening. Interference might happen in more general conditions, even ...
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Is the dimming of a phone screen under bright sunlight an example of destructive interference of visible light?

No. This is just because difference between white pixels and black pixels is overwhelmed by the sunlight that affects all pixels equally, and your eye can't tell the difference between white pixels ...
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What is the clear difference between interference and diffraction?

Feynman was likely referring specifically to the DSE/light and not waves in general. Diffraction and "interference" are clearly distinct. Water waves going thru a single slit DO diffract (...
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How does a rainbow show all of its colours?

The graphics just shows two raindrops, although of course there are lots of raindrops in between those two. It shows that every raindrop emits a bunch of rays, dispersed depending on the wavelength (...
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How does a rainbow show all of its colours?

When light hits the edge of the bubble (from the inside as well as from the outside), it can undergo a reflection as well as a refraction. So there can be several reflections inside the bubble before ...
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2 votes

What is the clear difference between interference and diffraction?

I didn't know this Feynman's quote, and to be honest it worries me a bit, because I didn't feel that there was a problem here, but Feynman usually was right! Here's, however, how I usually explain ...
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Are laser diffuse reflections really so dangerous?

Your calculation is fine, but it makes some assumptions that would be an unwise foundation on which to rest your eye safety. You assume that you are 1 meter away. This might be true most of the time, ...
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3 votes

Are laser diffuse reflections really so dangerous?

imagine...I shine it on a white wall. How small is the spot? With a lens to focus it, you can focus all of that energy onto an incredibly tiny spot. Let's now say that I am at 1m distance from the ...
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Finding Shift due to Refraction in Multiple Slabs when the object and viewer are in different medium

All you would need to do is assume that a cuboid is formed between the object and the first glass slab and that another cuboid is formed between the last slab and the viewer. You may then assume these ...
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1 vote

What lenses are generally used to focus a beam of light into a horizontal line?

If you look at their documentation, you will read this: Laser scanners – often referred to as profile sensors – use the laser triangulation principle for two-dimensional profile detection on ...
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1 vote

Can we tell on which side of a lens an image appears?

Yes, as shown below. Assuming the object is on the other side of the lens compared with the eye a virtual image is formed on the same side as the object whereas a real image is formed on the the ...
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Difference-frequency-generated (DFG) spectral width

Difference frequency generation (DFG) is a stimulated parametric down-conversion process, which implies conservation of energy. It manifests in the relationship among the frequencies of the three ...
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Can we tell on which side of a lens an image appears?

The image is like a copy of the object (with appropriate scaling) at the location of the image. In particular, it produces the same depth cues as a real object would. If you can see both it and the ...
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2 votes
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How do retinal cones see color when the cones pickup photons and not waves?

The interaction between photons and chemistry, eg, via atomic orbitals of single atoms, is a classic tool for understanding quantum mechanics, so there shouldn't be any surprises that the absorbing ...
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Sign Convention in Ray Optics

As I recall, if you are using the simple lens or mirror formula, the distance from a real object or image to the refracting surface is assumed to be positive. With a virtual object or image, the ...
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2 votes

How is this circular pattern of a streetlantarn behind a tree formed?

The branches may be randomly oriented, but the light is only strongly reflected perpendicular to the direction of the branch. Those branches that point more or less toward the lamp (from your ...
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3 votes
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Non-parallel light diffraction

Yes it does. A common version on the double slit experiment is, in fact, the one you describe. You can, for instance, install a narrow hole with the primary light source behind it. This hole will act ...
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Geometric optics explanation of lateral (transverse) chromatic aberration

You are correct that the first picture is wrong. For a single refractive lens, the lens power will be greater for blue light, compared to red. Hence the focal length will be shorter. You are on the ...
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Why do we see a blurred image when the screen is not placed at the position where the image is formed by a convex lens?

This answer isn't meant as a complete answer, just to give some more intuition in addition to the other answers. You don't need complete focus before an image is formed. Consider for example color ...
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Images formed by a pair of plane mirrors

Actually only 5 images will be formed if more images are drawn they will overlap the existing ones if drawn with perfect geometry.
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Do prescribed glasses transmit light?

Without light transmission, you will not be able to see anything since light is the way of transmitting the picture to your eye.
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2 votes
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Mirror Equation for convex mirror

What you have done is correct. We have to judge the diagram by obtaining the results from the formula but not just simply imagining a diagram. The results suggest that your diagram was wrong and the ...
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Concave mirror and convex mirror placed facing each other

You are struggling with sign convention in optics. That is really frustrating. In the figure $l$, $x$ and $f_0$ are all positive (as they should be in normal world) Applying mirror equation for first ...
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-1 votes

Why image of vertical object is always a straight line and perpendicular to principal axis?

So I think what you mean is why is the image assumed to be perpendicular to the surface it is standing on... And it is not slanted or curved as you have demonstrated in your second diagram. My ...
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What exactly does it mean when a light ray is incident on a surface?

Yes it does mean the angle with the normal.. in this case an incident angle of 30 degrees would mean the incident ray (the light ray flaling on the reflecting surface) makes as angle of 30 degrees ...
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What is the wavelength of light in a practical sense?

The question seems to focus on the relation between the source of an EM wave and the wave itself. Without think of sources, the wave length of a light beam can be identified by interference effect. ...
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2 votes

What is the wavelength of light in a practical sense?

Lets look at this Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. This 3D animation shows a plane linearly polarized wave ...
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Why image of vertical object is always a straight line and perpendicular to principal axis?

The answer is that all points with the same distance $u$ image onto different points but with the same distance $v$. You can ask, "ok, but why", and the proof to that is actually not shown ...
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What is the wavelength of light in a practical sense?

Define light. Visible light on the electromagnetic spectrum, More simply, the range of wavelengths is called visible because We can see it, and as such the human eye can detect wavelengths from 380 to ...
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-1 votes

Why image of vertical object is always a straight line and perpendicular to principal axis?

You draw it vertical because you are looking at your screen that is vertical (perpendicular to the optics axis). Edited: it's due to the fact that a lens in the optical limit has a focus $f$ and if ...
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What is a general definition of impedance?

Riding a bicycle with multiple gears is an exercise in impedance matching. The right gear will maximize the transfer of the rider's efforts to the motion of the bike. Choosing a gear that is too high ...
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What is a general definition of impedance?

The key to the original question is the askers mention that it was always met in wave behavior situations-periodic functional solutions. The periodic behavior is a strong constraint place upon two ...
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2 votes

Beam splitters- Direction of use

there is actually a difference between the two cases other than the diection of the reflected beam. Cube beamslpitters are constructed using two parts glued together using a special cement. The mirror ...
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What is the difference between MOKE hysteresis loop and VSM Hysteresis loop?

MOKE is an optical technique that relies on the rotation of the polarization of light incident on a material with a nonzero magnetization. It is typically used for 2 dimensional materials. VSM is a ...
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I have been told that in an xyz plane.The normal on incident point is given,how do I visualise a normal which is like this

I'm not sure what you're asking, but :$$\frac{\hat i + \hat j }{\sqrt{2}} = \frac{1}{\sqrt{2}} \hat i + \frac{1}{\sqrt{2}} \hat j$$
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Interference and diffraction pattern without lens

A double slit arrangement is shown below with the single slit often omitted is the light source is a laser. . You will note that interference occurs everywhere to the right of the double slit so ...
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