All Questions
Tagged with frequency visible-light
145 questions
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Why aren't brightness and loudness represented as spectra? [closed]
I'm curious why brightness (light intensity) and loudness (sound intensity) aren't usually described using a spectrum, which typically shows frequency ranges. Are these quantities measured differently ...
1
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1
answer
100
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Why does the energy (and thus frequency) of a photon entering glass stay constant if some is used up to accelerate electrons and slow down the light?
I'm learning optics and have been told that when light enters a medium (e.g. glass) and slows down the frequency of the light stays constant while it is the wavelength which is reduced. The ...
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1
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Why do we see objects with a given color?
I'm currently studying Electromagnetic Optics, and I don't quite understand the (classical) process through which we perceive an object with a given color. From my understanding, I'd make a ...
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6
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Why color depends on frequency and not on wavelength? [duplicate]
To explain my question lets consider this example:
The wavelength of light in a medium is $\lambda=\lambda_{0}/\mu$, where $\lambda_{0}$ is the wavelength in vacuum. A beam of red light ($\lambda_{0}=...
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Let's say I have manufactured a prism from a non-dispersive medium, then light coming from air wouldn't split into colours right?
Let's say I have manufactured a prism from a non-dispersive medium, then light coming from air incident on the prism wouldn't split into colours, right? I mean light still changes direction, but all ...
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Does our sense of color depend on frequency of source or the wavelength of light?
I was taught that the colors we see are results of the corresponding wavelength, but each wavelength also has a distinct frequency since speed of light is fixed for a specific medium (same goes for ...
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98
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Does two same light bulbs produce light of same frequency? [duplicate]
If they do, then why don't we observe interference in normal rooms? And if they don't have the same frequency then why is that so?
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2
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106
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What is the colour of an atom? [closed]
We know that when an electron jumps from shell to shell it produces light waves which produce the sensation of vision to our eyes. But can anything be said about the colour of an atom in particular. ...
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Does Color change happen under a prism? [duplicate]
I was watching this video.
It Showed that light ( green ) changes its color to red after incidence of light. I couldn't think of how this happens because light's color is dependent on frequency rather ...
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1
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How do i calculate change of momentum when I send a photon in the direction of travel
Say a spaceship is traveling at a certain velocity v (>>c) and it emits light from the nose of my spaceship in the direction of travel. The speed of light is finite and hence there should be a ...
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Snell's law and what determines color of light
White light is dispersed by a prism into the colors of the visible spectrum with wavelengths ranging from violet 380 to red 750 nanometers. By Snell’s law, the refractive index $n_{21}=n_2/n_1=sinθ_1/...
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216
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Is the intensity of a light wave related to frequency of the wave?
My problem is: How can I resolve these following ideas?
Energy of photons in an EM wave is proportional to the frequency of the wave
Intensity of an EM wave is proportional to the energy that is ...
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Would slowing down a beam of light change its wavelength and frequency?
I confess that I have little knowledge of physics, so this kind of thing really often goes over my head. However, I did read somewhere that the speed of a beam of light is the product of its ...
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Change of light from not visible to visible
Can light from infrared or UV change to visible light when it passes through some other material?
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158
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Does colour of light depend on intensity of light? [closed]
By intensity I mean frequency of light
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How is it possible that the wavelength of a wave can change but the frequency remains the same? [duplicate]
When let's say a beam of light passes through a transparent glass surface, how is the wave able to maintain the same frequency but the wavelength changes ?
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1
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Is the Drapers point inaccurate?
Is the Drapers point faulty since an oven glows visibly red without it actually reaching Drapers point? When the Drapers point blackbody radiation frequency is calculated by Wien's law it results ...
user348071
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Do all objects at the same temperature glow the same color?
Does Kirchhoff's law for heat radiation imply that all objects at the same temperature will glow the same color?
In other words, if a piece of molten iron glows the same color as my body, which ...
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How many colours is light made up of?
How many colours is light made up of?
Should it be infinite because of colours like light-blue , fluoroscent-blue , cyan ,dark green , sap green , etc.?
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286
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What is the wavelength of red light in vacuum?
According to Wikipedia,
It has a dominant wavelength of approximately 625–740 nanometres.
However, I'm not sure in which medium this wavelength was measured. Was this wavelength measured in a vacuum?...
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1
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136
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What happens to the time period when refraction occurs? [duplicate]
I was studying light and had a doubt that when refraction occurs (rarer to denser just assuming) then frequency remains same but lambda (wavelength) and velocity decrease. But I cant quite figure out ...
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If frequency of light never changes, is there finite number of blue light, red light, etc.?
AFAIK light's frequency cannot change. If that is the case, would it mean that there is a finite amount of every frequency floating around in the universe? ie. some finite number of 400hz light rays, ...
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Why didn't I experience violet shift at traffic signals?
context: we were studying sound waves and our instructor informed us about doppler effect and violet shift of light. Now I have many times exceeded the speed limit at night where there were no cameras ...
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What's the mechanism of addition of different frequencies of light?
I suddenly thought of a interesting thing:
say there are two light rays with the exactly the same colour, for example, purple. Red light ray and blue light ray add up to purple. Also, there is a ...
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Is the temperature of light affected by color filters?
This video demonstrates how varying color filters alter the energy of photoelectrons emitted from a light source:
https://www.youtube.com/watch?v=kcSYV8bJox8
But I am confused by what these different ...
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2
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Can monochromatic light have units of per frequency?
Plank outlines (page 209, equations 302-304) in his book that a monochromatic ray of frequency $v$ is has intensity of
\begin{equation}
I_{\nu} = \frac{2 h \nu^{3} F \Omega}{c^{2}} \left( e^{\frac{h\...
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5
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Why does light have multiple frequencies?
The wavelength of visible light ranges from 750 - 400 nm, and so do the corresponding frequencies. However, a photon only has one frequency, given by $E =h\nu$, at a given time, and it can’t be ...
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Is light a single wave when we refer to frequency?
When we say that light oscillates $n$ times (frequency) in a second do we mean that the same electromagnetic field travelling through space oscillates $n$ time's? As i have seen diagrams suggesting ...
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2
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367
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What is the wavelength of white light? [closed]
Does white light have a wavelength, and I know that the sun emits white light, but the atmosphere makes it refract to make it appear yellow to us. Do all the stars in the universe emit white light?
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543
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Why refractive index of same material is different for different monochromatic lights?
Yeah I know that refractive index is different for different monohromatic lights due to the change in velocity of light. And as frequency doesn't changes and only wavelength changes while travelling ...
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What does the amplitude of a light wave tell us? How's it different from light intensity in a physical sense?
In my understanding, the energy of a photon, in wave terms, just translates to the frequency of the wave. If I make a photon with more energy, it will use the extra energy to just oscillate faster.
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Is there a finite number of colors in the visible spectrum? [duplicate]
Does quantum theory and Planck's length of $1.6\times10^{-35}\ \mathrm{m}$ mean that the electromagnetic spectrum is not continuous as every photon can only carry a discrete amount of energy?
If so, ...
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Frequency of EM waves
When light travels in air, all the component frequencies of light travels with the same velocity $v_{air} = 1/\sqrt {\epsilon_0\mu_0}$ (where $\epsilon_0$ is independent of frequency. Then we say that ...
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What does the "true" visible light spectrum look like? [closed]
When I google "visible light spectrum", I get essentially the same image. However, in each of them the "width" of any given color is different.
What does the "true" ...
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Why is the color of light not associated with frequency?
Imagine a green light source is at the center of a transparent material sphere and I am staying in the vacuum (or air) and looking to it.
Now imagine that the wave length of the this light increases ...
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How do we know that human eye reacts on frequency of visible light rather than on some other parameter? [duplicate]
This is a very basic question in optics: why the mathematical language we use corresponds to what we actually see.
There are (at least) two ways to think of a decomposition of a visible light.
One way ...
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Do gravitational lenses act as prisms?
Light creates gravity, and the greater the light's frequency, the greater this gravitational effect is. It stands to reason then that light of different colors would react slightly differently to ...
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1
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Can l apply force using light wave? [duplicate]
Can I make light dig a hole by increasing it's frequency? Can I relate force with wave using the equation $c=$ wavelength$\times$frequency?
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1
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107
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Which fact is true about the speed and frequency of light?
I am totally stuck over this concept and google doesn't help.
First, We say that light's speed is constant for all colors in vacuum but different in all other media. Then which color's speed are we ...
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1
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291
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What is “spectral turnover”?
In a paper which deals with the spectra of radio frequency cosmic events, the word “spectral turnover” is used. What is “spectral turnover”?
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3
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528
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Comparing a 100W and a 40W light bulb that only emits a specfic frequency
I'm sort of confused by this... let's just say the bulbs only emits green light, and we compare a 40 W and 100 W bulb (identical except one is brighter than the other), since the frequency of light ...
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2
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271
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Intuitive Explanation for Doppler effect?
I was looking for an intuitive explanation as to why the Doppler effect happens. I haven't found any, but this is what I thought:
-Waves emitted travel at a constant speed
-The source emits a wave
-If ...
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4
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Are monochromatic EM waves supposed to be sinusoidal?
This question remind me of a doubt on the relation between colors and frequencies.
When we talk about a monochromatic color of a given frequency (or at least a narrow range of frequencies), it means ...
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Is there a way to calculate frequency of visible white light? [duplicate]
According to Wikipedia visible light lie between 405-790 THz https://en.wikipedia.org/wiki/Visible_spectrum
Can I just sum "maximum" spectrum of the light if by definition white light is sum of ...
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7
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What really determins the color of light? [duplicate]
I have been considering this problem:
Colour is characterized by which of following character of light?
a)Frequency
b)Amplitude
c)Wavelength
d)Velocity
Different websites claim ...
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6
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How can a red light photon be different from a blue light photon?
How can photons have different energies if they have the same rest mass (zero) and same speed (speed of light)?
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Would visible light still be in a separate classification if we saw "colors" in a different wavelength? [duplicate]
Basically im asking if there's anything special about visible light other than the fact that we use it to see colors. If we saw in another wavelength, would it still be possible to see colors like we ...
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Number of Possible Frequencies in Visible Spectum [duplicate]
Quantum physics says that energy is quantised, and since the energy of a photon is only dependent on the wavelength, the wavelength of a photon is quantised. This means that even though an infinite ...
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2
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42
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Is their a way to protect screens from being recorded? [closed]
This idea might sound stupid but...
Is there a way a screen would be impossible to record using a prism? I’m not talking recorded by a software but recorded from a camera…
If you put a prism layer in ...
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4
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How exactly is white light a combination of several wavelengths? [duplicate]
I have read that light is an electromagnetic wave. Every ray of light has a specific wavelength. The colour perceived by any observer is dependent upon the wavelength of the incident light.
What I ...
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