All Questions
Tagged with absorption visible-light
98
questions
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44
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What is the range of noon sun color temperature, when a light meter reports full expected sunlight (+/- epsilon)?
My question came from trying to find what uncertainty bounds, if any, I can assign to a color temperature sensor, without access to an artifact with a precisely calibrated output spectrum.
This leads ...
- 11
1
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1
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57
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Absorption spectra in films chemicals & dyes
For a science competition, we have to understand absorption spectra in films chemicals & dyes. But what is that? I've found resources on the absorption spectra of chlorophyll, but I'm unclear as ...
- 187
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4
answers
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Aren't places where geodesics end singularities?
So of course when stuff falls into black holes, the geodesic for anything ends in that singularity. However, isn't it technically true that a light ray that originates from the sun and then hits the ...
- 1,534
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2
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58
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Why do the proteins in our eye have a continuous (bell shaped) absorption spectrum?
From quantum physics, I would expect that seeing e.g. red would excite the 564nm energy level of the Photopsin protein. I would also expect to only see (apart from some small smeering out) that we are ...
- 37
1
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106
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450nm peak absorption [closed]
I am looking for an oxide compound (metal oxide, or similar preferably inorganic) which shows light peak absorption at 450 nm. I have troubles in finding the right compound, as most of the oxides have ...
- 113
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18
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What effect, if any, does dissipative absorption have on aurora borealis? Why don't we see more colors as a result?
According to wikipedia, the aurora borealis is primarily caused by charged particles from the solar wind being redirected to the poles by earth's magnetic field and slamming into the nitrogen and ...
- 57
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13
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Why do the 'colors' of liquids in differently sized glass cylinders appear similar despite varying absorption rates?
For some liquids, such as cooking oil, I have observed that when filling two glass cylinders (with lids) of different diameters (e.g., one with a 5 cm diameter and another with a 10 cm diameter) with ...
- 382
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85
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How does light absorption work for solids and liquids?
I've studied in my physics class, absorption and emission spectra for gases or more "spread out" molecules like what is done in atomic absorption spectroscopy (learnt that one in chemistry). ...
- 11
2
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57
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Predict color of dye under a certain wavelength of light?
I am picking fluorescent dyes to be put under a UV of known wavelength and would like to be able to predict approximately what color the dyes will appear under the light. I can request ...
- 21
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2
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408
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If photons are massless, how are they reflected and blocked by something that has mass? Shouldn't they pass right through any object?
If photons are massless, how do they get reflected, blocked when something comes in its way? Shouldn't the particle just pass right through any object?
- 341
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12
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Expansion and visibility of particles because of diffusion
A cloud forms as a point source containing a fixed quantity of
particles and then expands according to the diffusion equation. Let's
analyze how the visible size of the cloud changes with time. When ...
24
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4
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8k
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Why can't sunlight reach the very deep parts of an ocean?
Sunlight reaches the surface of the ocean and refracts. So it is still there. And its speed is about $225000$ km/s in water which is still incredibly fast. Light is a massless electromagnetic wave. So ...
- 402
2
votes
2
answers
237
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Why does light either get reflected, absorbed, or passes through a surface or obstacle?
For each of these 3 cases, I'm having trouble understanding...
If light is reflected, does that mean that there was not sufficient energy by the photons to excite the electrons of the surface to ...
- 195
1
vote
1
answer
361
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How does light interact with atoms? [closed]
I've read this answer regarding the difference between mere reflection and absorption followed by emission and I am struggling to understand some concepts. To begin with, we have some matter-light ...
- 11
-3
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132
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Does colour of light depend on intensity of light? [closed]
By intensity I mean frequency of light
- 11