The wavelength tag has no wiki summary.
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What determines color — wavelength or frequency?
What determines the color of light -- is it the wavelength of the light or the frequency?
(i.e. If you put light through a medium other than air, in order to keep its color the same, which one would ...
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6answers
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Why is air invisible?
I think that something is invisible if it's isolated particles are smaller than the wavelength of visible light. Is this correct?
Why is air invisible? What about other gases and fumes which are ...
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4answers
786 views
What causes polarised materials to change colour under stress?
Our physics teacher showed the class a really interesting demonstration. He used two polarised filters in opposite orientations, then he took some antistatic tape and stretched it under the two ...
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3answers
810 views
Why is it necessary for an object to have a bigger size than the wavelength of light in order for us to see it?
I keep hearing this rule that an object must have a bigger size than the wavelength of light in order for us to see it, and though I don't have any professional relationship with physics, I want to ...
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Why do rainbows have distinct colors?
When I searched on the Internet for the reason of formation of rainbows, I got many explanations like this one & this. All the explanations consider only one spherical water droplet (like this ...
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3answers
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Is there a light source that emits all wavelengths of visible light at the same time?
Many light sources like LEDs and lasers only emit a single wavelength of light.
Is there a light source that emits all wavelengths of visible light at the same time?
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2answers
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Why is Near Field Communication (NFC) range limited to about 20cm?
Near Field Communication (NFC) operates at 13.56 MHz.
Near Field is the region situated at a distance r << λ
λ = c/f
...
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4answers
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Light emitted by an object according to its temperature
According to this picture
the light emitted by an object depends on its temperature.
That makes perfect sense when we heat a metal. As its temperature raises we see it red at first, then orange, ...
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2answers
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De Broglie wavelength, frequency and velocity - interpretation
Two fundamental equations regarding wave-particle duality are:
$$ \lambda = \frac{h}{p},
\\
\nu = E/h .$$
We talk about de Broglie wavelength, is it meaningful to talk about de Broglie frequency ...
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2answers
190 views
If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?
So, my understanding is that the wavelength of a photon is the distance traveled in the time it takes it's magnetic field to oscillate. And it's inversely proportional to it's energy and it's ...
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2answers
545 views
What is the minimum wavelength of electromangetic radiation?
As a first approximation, I don't see how a wavelength of less than 2 Planck distances could exist. The question is: are there any other limits that would come into play before that?
For example:
...
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3answers
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Does light change color on its way through a window?
Looking at the refractive index of glass, it's around $1.6$.
Then the speed of light $x$ through light should be given by
$$ 1.6 = \frac{3.0\times10^8}{x}, $$
so $x$ is about ...
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2answers
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Why does wavelength change as light enters a different medium?
When light waves enter a medium of higher refractive index than the previous, why is it that:
Its wavelength decreases?
The frequency of it has to stay the same?
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2answers
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What's the difference between dim and bright light?
When comparing two light sources, for example, a light bulb at 20W and a light bulb at 100W, what is it about the incoming light that makes the latter look brighter than the former? Are there ...
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3answers
159 views
What if $\gamma$-rays in Electron microscope?
I was referring Electron microscopes and read that the electrons have wavelength way less than that of visible light. But, the question I can't find an answer was that, If gamma radiation has the ...
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2answers
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In electromagnetic radiation, how do electrons actually “move”?
I've always pictured EM radiation as a wave, in common drawings of radiation you would see it as a wave beam and that had clouded my understanding recently.
Illustration on the simplest level:
...
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2answers
317 views
Magnetron limits
What are the practical limits on generated wavelength in a Magnetron?
We know that Magnetrons could be used efficiently for generating microwaves for water heating, or for radar applications, but ...
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2answers
75 views
How does the wavelength change in relativistic limit?
In the text, it reads that the momentum of a particle will change if it is moving at speed close to light speed. In the general case, the wavelength is given as
$$
\lambda = \frac{h}{p}
$$
and
$$p ...
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1answer
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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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1answer
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Is the number of wavelengths of light spanning a distance invarient with respect to spacetime distortion?
I was recently asked by a friend how the expansion of spacetime effects photons. I gave him what I feel is a satisfactory general response, but it got me wondering how, exactly to calculate this ...
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2answers
403 views
Is all kind of light same speed?
Is there any speed different between blue or red color? Is there speed different? or there are same speed?
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2answers
241 views
Why does Planck's law for black body radiation have that bell-like shape?
I'm trying to understand Planck's law for the black body radiation, and it states that a black body at a certain temperature will have a maximum intensity for the emission at a certain wavelength, and ...
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3answers
199 views
Why aren't the graphs for black body radiation straight lines?
We know that a wave which has greater frequency will have low wavelength and high energy. So, by decreasing the wavelength, the frequency and consequently energy (intensity) of that wave will increase ...
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3answers
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What was the motivation behind suggesting the trichromatic theory of vision?
Background
In this thread, I asked whether it is true that the colors red, green and blue, through additive mixture, can make up any color. Turns out they can't.
However, when reading about the ...
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3answers
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Some questions about car radio and cellphone antennas
1-Why the antenna of the radio of cars is located outside the car and not inside?
2-If the answer to 1 is because that cars are like Faraday cages then how come my cell phone can receive signal ...
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1answer
307 views
Generated wavelength of free electron laser
Could you please help me understand how one can measure output frequency of free electron laser (provided that we know size of magnetic domains and electron energy)? This should be a function of ...
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3answers
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Radio antennas that are much shorter than the wavelength
From my limited experience with ham radio when I was a kid, I expect transmitting and receiving antennas to have lengths that are on the same order of magnitude as the wavelength, and in fact I recall ...
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1answer
461 views
Visible light spectrum to color space
I need to be able to convert an arbitrary emission spectrum in the visible spectrum range (i.e. for every wavelength between 380 and 780, I have a number between 0 and 1 that represents the ...
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1answer
74 views
Holograms? Sci Fi or future fact?
Based on how light behaves when it passes through mediums, i.e. the wavelength of light changes when it passes through mediums of different refractive indexes, wouldn't it be possible to convert ...
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3answers
307 views
Does the wavelength always decrease in a medium?
I was studying a GRE Physics Test problem where optical light with a wavelength of 500 nm travels through a gas with refractive index $n$.
If we look at the equations for wave motion and index ...
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1answer
74 views
Understanding de Broglie Wavelengths
I understand the derivation and calculation of de Broglie wavelengths, but what exactly does the wave of a particle represent? What does the wavelength of a particle mean? I'm assuming it's not the ...
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0answers
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Optics: finding total power of a syste, including wavelength
Specifically I need to create an ABCD matrix given 2 radii of curvatures, the thickness of the lens, type of glass (BK7) and a given wavelength. I will have to figure this out eventually, so help ...
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2answers
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Frequency of the sound when blowing in a bottle
I'm sure you have tried sometime to make a sound by blowing in an empty bottle. Of course, the tone/frequency of the sound modifies if the bottle changes its shape, volume, etc.
I am interested in ...
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1answer
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What's the wavelength of an electron after hitting a potential barrier?
I have this question:
An electron with Energy $E = 40 eV$ hits a potential barrier with $E_0 = 30 eV$. What is the wavelength of the electron after hitting the potential barrier?
I worked from ...
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1answer
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Does interchangeable wavelength LED exist in NIR?
Does exist a led material that allow to interchange the emitted wavelenght in near IR spectrum?
Thanks
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1answer
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Finding the wavelength of an electron in its ground state?
To find the wavelength of an electron in its ground state in a hydrogen atom, would I or could I do the following?
Use the ground state energy (-13.6eV) in $E^2 = m^2c^4 + p^2c^2$
Solve for $p$
Use ...
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1answer
290 views
Laser Coherence Length/Time
Scenario:
Imagine a collimated beam of white light falling on one refracting face of a prism. Let the light emerging from the second face be focused by a lens onto a screen. Suppose there is linear ...
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1answer
636 views
Find the dispersion of the slab?
I've been having trouble with this for a few days and already used up all my tries on the homework for it, but have the final is coming next week. Thus I would like to know how do this, however I ...
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1answer
112 views
Will a photon emitted from something moving quickly have a shorter wavelength?
If a photon is emitted from a light source moving at any speed, the photon will nonetheless always move at c (assuming it is emitted in a vacuum.)
If the speed of a photon's emitter cannot influence ...
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1answer
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Is the de Broglie wavelength of a photon equal to the EM wavelength of the radiation?
Is the de Broglie (matter) wavelength $\lambda=\frac{h}{p}$ of a photon equal to the electromagnetic wavelength of the radiation?
I guess yes, but how come that photons have both a matter wave and an ...
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0answers
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How does a Fresnel rhomb work (half and quarter wave plate)?
How does a Fresnel rhomb work (half and quarter wave plate)?
I am aware of birefringence, which creates a phase shift of $\Delta\phi=\dfrac{2\pi\Delta nL}{\lambda_0}$. But this doesn't explain how a ...
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0answers
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How do you super impose two or more signals to occupy a fix area of space with the resultant summed wave?
Is it possible to super-impose two or more signals all sent from different directions as a standing wave with the resulting summed wave occupying a fix area of space that is also a complex area?
Do ...
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2answers
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Is carbon dioxide a greenhouse gas? [duplicate]
Possible Duplicate:
What experiments prove the greenhouse effect?
I am seeking for a proof that CO2 is a greenhouse gas. I posted this on Skeptic.SE recently but found no help in seeking ...
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2answers
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Can the equation $v=\lambda f$ be made true even for non sinusoidal waves?
The known relation between the speed of a propagating wave, the wave length of the wave, and its frequency is
$$v=\lambda f$$
which is always true for any periodic sinusoidal waves.
Now consider:
...
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2answers
485 views
Matter waves and de Broglie wave length
The wavelength of a particle of momentum p is calculated using De Broglie relation.
The de Broglie relation was postulated for what is called a matter waves. Now according to the statistical ...
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2answers
131 views
Wavelength comparison of two waves
Is there any non-digital (naturally existing) mechanism to compare two or more waves in such a way:
...
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1answer
127 views
Merge different wavelength rays
Let's say an array of rays of light is given.
Each ray has a specific wavelength (in the range of visible light).
Example:
...
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0answers
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UV light penetration into silicon
I'm in need of some information about UV (particularly UVA) light's ability to penetrate into silicon. Specifically, I am looking for a relationship between wavelength and penetration depth. Also, if ...
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Low Frequency Standing Waves in Cylindrical Structures [closed]
What would be the frequency of the fundamental vibration in a 50 meter tall cylindrical structure if it were closed at the bottom?
L = wavelength/4 for closed end cylinders so the wavelength I ...
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1answer
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The wavelength of a brainwave [closed]
Wavelength = (speed of wave)/(frequency). If a brainwave is at 7 Hz. then the math is (299,792,458 meters per second)/(7 Hz.) = 42,827,494 meters. The speed of wave or phase velocity is using the ...
