Questions tagged [reflection]
This tag is for questions relating to reflection, the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated. A familiar example of reflection comes from water waves; as the waves travel they reflect off objects that are floating in the water, and also reflect off the walls of the container holding the water.
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Why does LIGO use an IR laser?
The phase difference at the beam splitter of a LIGO-like interferometer is given by
$$ \Delta \phi \simeq \frac{4\pi}{\lambda} h L\ , $$
where $h$ is the gravitational wave strain (assuming a ...
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Action of a Barrier on a Wave [closed]
I know that when a wave encounters a barrier, change in medium, or even a discontinuity in the medium then a reflection, and transmission of the wave occur. When a wave encounters a barrier or change ...
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At the cutting edge of 25m telescope design would smaller but much more numerous mirrors be an option?
I am not in the field of astronomy or optics. Therefore I don’t claim anything but curiosity. That being said I would imagine several to many advantages to an array of mirrors smaller than 8m (...
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Reflection of wave from a ring of finite mass at one end of a string
While reading about reflection of waves from a fixed (mass of ring=infinite) and free (mass of ring=0) end, I noticed that in the first case, the wave behaves as though a wave in the same phase and ...
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Evanescent Field converted to light
I have a question about evanescent fields: It is widely known that if laser light enters a prism at an angle larger than the critical angle, then it will experience total internal reflection. ...
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Method of images for a spherical acoustic source near an impedance interface
Rigid boundary (review)
Consider an infinite, perfectly rigid surface located at $z \geq 0$. A point acoustic source is located in the lower half-space at $z = -a$, sending out a spherical wave with ...
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Is a wall transparent to visible light only one way possible?
I'm thinking about theoretical possibility of some wall (rectangular 3D object) that let electromagnetic radiation of certain wavelength band (e.g. visible light) through retaining (almost) same ...
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Resolution of Virtual Image on Camera Lens: Total Path Length versus Angular Extent (relative coverage of lens's field of view) of Reflected Light
For an upcoming DIY project, I have some constraints that can be reduced to the following diagram:
In words, there is an object ($\color{green}{\text{green}}$ rectangle) with a specific feature (...
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Perfect Reflection of Light
I want to make an object that has a perfect reflection.
I know that an atom will absorb light by causing electrons to move from a lower energy level to a higher, "excited" energy level. I ...
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Would reflections make an electromagnetic wave more penetrating into metals?
First i should clarify how i arrived at this question. I understand that in the case of an EM wave reflected off a higher refractive index surface, the reflected electric field vector changes ...
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Relationship between Radius of Curvature and focal length of a spherical mirror without approximation [duplicate]
I have seen tons of videos on the matter but all of them prove $R=2f$ which requires an approximation. I have known and used a result $f=R/2(1-sec(θ))$ but am unable to prove it.
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Number of images (non-divisible angle) [closed]
I have a question where there is a pair of plane mirrors in a plane with angle 'T'.
Now T, is not a divisor of complete angle Ex: 181 degrees, 97 degrees. Now we will have a defective area because the ...
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How is this kind of rainbow formed?
Earlier, I saw this rainbow out of my window:
Sorry for the meagre quality. As you can see, there is a primary rainbow, but directly attached below the primary rainbow, another, fainter and thinner ...
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Do higher-order virtual images between two mirrors move faster than light?
I was studying the case of an object placed between two plane mirrors. Whenever a object is placed between two parallel mirrors, the distances between the successive images is found using the criss-...
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What determines whether solar panels are blue or black?
Some solar panels are blue, and others are black. I'm finding (seemingly) conflicting information online about why. (I'll ignore the tiny minority of solar panels that are deliberately colored some ...
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