Questions tagged [refraction]
Change in the direction of propagation of a wave when its transmitting medium changes.
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Why do the LINES in a vertical soap bubble get thinner as we go down?
I understand that the soap bubble gets thicker at the bottom of the bubble due to gravity, resulting in a complicated array of different colors of different wavelengths being constructively and ...
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Measuring inner choke point on non-uniform silica capillary tube
I hope this is an appropriate place to be asking questions like these (google brought me here when I was searching for a solution)! I make an assembly where a small silica capillary tube (OD of 1mm) ...
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1answer
55 views
Why does a rainbow only form with a 42° angle? [duplicate]
Why do rainbows only form with a 42° angle? Is there something special about this angle?
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1answer
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Dielectric constant change in the atmosphere?
I'm curious about the refractive index changing in the atmosphere. As I understand it (and I may very well be wrong/naive) when a ray of light enters from one medium into another, the electric field ...
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2answers
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Do mirages really occur due to total internal reflection?
Mirages occur in areas such as deserts due to difference in the refractive indices of layers of air. As the light ray travels from denser to rarer layers of air, slowly bending, it approaches the ...
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1answer
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Path of sound in ocean where sound speed varies linearly with depth
In an ocean, described with $x-y$ Cartesian coordinates where $y=0$ on the sea bed, the sound speed varies linearly with $y$:
$$v(y)=c+by$$
A textbook says that, if sound wave is emitted on the sea ...
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Thickness and refractive index of silica gel layer between fused silica and water interface
I learned that when fused silica contact with water, a layer of silica gel will be formed. However, I cannot find any reference about the thickness and the refractive index of the silica gel. Can ...
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2answers
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Snell's law and Fermat's principle
I have read this sentence on a book about the Snell's law of refraction, referring on a ray that passes from air ($n_1=1$) to glass ($n_2=1.55$):
"Snell's equation can be derived from Fermat's ...
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1answer
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Bending a Laser Beam [closed]
We can bend a Laser beam by varying the refraction coefficient of the air.
We can bend a Laser beam by dispersing into the air small particles that have the same effect on the Laser Beam and small ...
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2answers
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Are there any real-world examples of refraction of light by magnetic permeability?
The question Fresnel Transmission Coefficient for Magnetic Field is interesting.
Thinking about it led me to reflect upon what little I know of the history of optics, with refraction by lenses and ...
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2answers
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Why does violet light bend the most? [duplicate]
When white light passes through a prism, refraction occurs and it splits into its seven constituent colours. If the spectrum is obtained on a screen violet light appears much more bent than red light.
...
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1answer
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Correlation between the refractive index and the density
The $v$ propagation speed of light in a transparent medium is related to the $c$ speed of light in vacuum through the relationship,
$$\boxed{n=c/v}$$
The constant $n$ is a pure number called ...
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2answers
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Angles of Refraction,Internal reflection and incidence
First ill ask my question in brief and then ill elaborate it below...
Theoretically is it that internal reflection occurs within a solid sphere(which is considered to be the denser medium) if and ...
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2answers
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Do gravitational waves disperse/refract (like EM waves in a prism)?
I have read this question:
What is the relationship between a gravitational wave and a graviton?
where kingledion says:
Gravitational waves were theorized a century ago and recently ...
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1answer
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Calculated focus of an asymmetric bi-convex lens
So I've been working on modeling an optical system using ray tracing. I've finally gotten to the point where I am testing things however I've come across something I'm not entirely sure of. I'm ...
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0answers
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The Refractive Index of Water after Several Heating and Cooling Cycles
If the refractive index of water under a certain temperature, say 20 degreeC, is 1.33334. Will it return to exact the same value after one or several heating and cooling cycles? Or will it shift a ...
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1answer
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Phase difference and optical path difference (OPD)
My textbook says that $\frac{\delta}{2\pi}=\frac{\Delta L}{\lambda}$, where $\delta$ is the phase difference and $\Delta L$ is so called path difference. But that's a cheat in my opinion. Even if the ...
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4answers
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Reverse of diffraction
Can we arrange a practical in such a way that the dark and bright bands in diffraction grating be allowed to pass through the same slit to get the original light (i.e the incident light before ...
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Why frequency does not change when light passes through the denser medium? [duplicate]
as far as I noticed always people in physics have a predefined assumption that frequency is constant. whereas we know that the c is the outcom of product of wavelength and frequency. we have different ...
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1answer
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Why does the Complex Index of Refraction take part in the Reflection?
I'm aware that in Optics, the complex index-of-refraction $\eta = n+ik$ is used, which famously leads to the reflection property at an incident angle, i.e. Fresnel's law:
$$R=\frac{(n-1)^2+k^2}{(n+1)^...
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2answers
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Help understanding the speed of light in media with refractive index < 1
I have read the standard explanations on this, but I still have trouble with convincing myself that information is not propagating at faster than the speed c in media of refractive index less then ...
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2answers
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Changing Refractive Index
Is it possible that the refractive index of a material could change?if so,what are those factors and what kind of variation could they bring?
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Question about transmission of paraboloidal light waves in bi-convex lens
The question is as follows:
Show that a paraboloidal wave centered at $z_1$ is converted by a lens of focal length $f$ into a paraboloidal wave centered about $z_2$, where $\frac1{z1} + \frac1{z2} ...
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1answer
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Do photons “bounce off” of electrons?
I’ve been reading a book, and in one part the author explains how electrons only absorb the wavelengths of light that can take them to an excited state, i.e. that can take the electrons to a higher ...
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1answer
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How do I use a sunstone? How does it work?
I have acquired two pieces of Icelandic Spar (optical calcite) with surface and internal fractures that should be serviceable as sunstones.
I have observed the double refraction and cancelling double ...
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2answers
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How do we determine refractive index of a photonic crystal?
Normally, refractive index of a medium is defined as
$$n=\frac c{v_\text{p}},$$
where $c$ is the speed of light in vacuum, and $v_\text{p}$ is the phase speed of light in the medium. Phase speed is ...
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1answer
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Why does the intensity of the scattered light vary when a monochromatic laser is shined into a transparent object?
When a laser is shined into a glass ball such as this video (link) or a bottle of water (link) the light is refracted through the whole transparent body. However, the intensity of the light scattered ...
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2answers
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Is speed of light continuous when entering a medium?
I know that light has the speed $c$ in vacuum and speed $c/n$ in a medium with refractive index $n$.
I wonder how this exactly happens - is there some kind of smooth transition? If so, on which scale?...
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3answers
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Why doesn’t a normal window produce an apparent rainbow?
When light refracts in a prism it creates a rainbow. My question is, why don’t all windows or transparent objects create this dispersion, i.e. why is the refractive index dependent on frequency in a ...
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Polishing Spherical Refracting surface vs Lens
My text book states that
When we polish a spherical refracting surface (sphere) it doesn't behave as spherical surface and mirror .It still behaves as spherical surface. The polished side is just ...
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1answer
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(7) Will a nearsighted person who wears corrective lenses in her glasses be able to see clearly underwater when wearing those glasses? [closed]
Will a nearsighted person who wears corrective lenses in her glasses be able to see clearly underwater when wearing those glasses?
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1answer
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Physical Analogs of General relativity and optics
My Prof told me today there is a 1-1 correspondence between particles in a curved space time, and optics problems in various indices of refraction, extending even as far as black holes. Does anyone ...
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2answers
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Why does a prism refract light into a rainbow? [duplicate]
Why does a prism refract light such that the different frequencies of light “spread out”? The same goes for rainbows, why do the raindrops “spread out” the different frequencies of light?
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1answer
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Why light travels through shortest path during refraction?
I know in order to compensate with change in speed but how does Light actually know which path is less dense or more dense?
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4answers
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Why does frequency remain unchanged in light refraction but wavelength doesn't? [duplicate]
Since the frequency of an electromagnetic wave does not change during refraction but the velocity changes, the wavelength must therefore change. But why doesn't the frequency change in the first place?...
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2answers
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Can light possibly bend to the other direction of the normal?
When light goes from a more dense medium to a less dense medium, it bends away from the normal, as in the image
When light goes from a less dense medium to a more dense medium it bends towards the ...
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2answers
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Radio Waves / Light: Atmospheric Refraction
The following image differentiates between a visual horizon and a radar horizon.
Sidenote: I'm not too familiar with primary surveillance radar
technology, but this image refers to secondary ...
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3answers
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Why doesn't the wave's frequency change as it gets refracted? [duplicate]
I know that frequency means a complete wave produced per second. But when the wave gets refracted, it's wavelength decreases. If the wave's wavelength has decreased doesn't it means that the wave has ...
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0answers
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Dielectric constant in terms of fundamental forces [duplicate]
How can one explain the slowing down of electromagnetic waves travelling in a medium using fundamental forces of nature like electromagnetism?
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1answer
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Do clouds reflect radio waves?
Do clouds reflect radio waves? Specifically, those waves used in radars.
And, what kind of matter refracts or reflects radio waves?
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Raytracing on convex spherical surface, where n1>n2
I'm reading my textbook and I'm trying to figure the ray tracing of a single point of this one case that the book doesn't cover. My question is, what does the ray tracing look like when we have a ...
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1answer
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“Partial” Total Internal Reflection
Can partial TIR happen?
Consider the image present in this link
Here, at point D, TIR happens, but also there is transmission.
Is "total" internal reflection a misnomer?
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6answers
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Lorentz invariance of Maxwell's equations in matter
I know that Maxwell's equations of electromagnetism are Lorentz invariant in a vacuum. But what about in a generalized medium, e.g. a metal, a rubber, a dielectric, a magnet? I have read it comes down ...
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1answer
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Is it possible to calculate the refractive index of a gas mixture given the pressure, temperature and wavelength?
I am searching for a formula to calculate the refractive index at a specific point in a planetary atmosphere.
Given are pressure, temperature, wavelength and the molecular composition of the ...
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0answers
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Quantum mechanics of refraction and reflection? [duplicate]
I learnt that light bends when passing through different mediums is due to the epsilon which is how much the strength of electric and magnetic field in the direction of travel changes in the material, ...
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0answers
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Will the refractive index of a electrolyte change when chemical reaction happens?
Since polarization is the reason of refraction, then anything that changes the structure of molecule, atom, or electron will present as a change of reflection. Thus, to my understanding, chemical ...
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2answers
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Does light travel faster in between Casimir plates?
Speed of light is in general $c/n$ where $n$ is a refractive index. But for example introducing two parallel plates with very small spatial separation will perturb the energy density of vacuum ...
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1answer
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Griffiths Electrodynamics Problem 9.39: How can $\sin(\theta_T)$ be greater than one?
When an electromagnetic wave strikes an interface between two linear media, Snell's law states that $\frac{\sin(\theta_T)}{\cos(\theta_I)} = \frac{n_1}{n_2}$ where $\theta_I$ is the angle of incidence,...
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1answer
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Photoelastic modulator vs. Acousto-optic modulator
I am trying to understand the salient differences between photoelastic modulators (PEMs) and acousto-optic modulators (AOMs).
Both of these devices are based on the photoelastic effect - that is, ...
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1answer
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Refractive index and optical fibre question
This is an A level AQA question:
A signal is to be transmitted along an optical fibre of length 1200m. The signal consists of square pulses of white light and this is to be transmitted along the ...
