All Questions
Tagged with reflection thermal-radiation
24
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Would a hypothetical perfect reflector emit thermal radiation?
The question says it all. I believe a hypothetical perfect reflector is what's referred to as a "white body", but I might be wrong. From what I understand such a hypothetical perfect ...
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What is the albedo of our Sun?
I think the Sun is the closest to a perfect natural black body we can get in the Solar System, if so then what happens to the light if I point a laser pointer at the Sun?
- 13k
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Are there any material coatings that would currently be effective to counter the rise of directed energy weapons?
I've been reading into directed energy weapons recently, and they seem like they're going to be a gamechanger. I'm just curious as to material countermeasures. I've learnt that some dielectric mirrors ...
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Why does gold only glow red after flame is removed?
I was at a jewelry workshop today and saw somebody place a gold ring under an intense flame. Weirdly, the ring looked normal when underneath the flame, but glowed "red-hot" as soon as the ...
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Is it possible to raise an object's temperature by reflecting or absorbing and re-radiating its own radiation back on it?
I am a layman with a little beginners knowledge.
This question is an effort to prove or disprove the Greenhouse Effect (GHE) theory as this is the basis of "back radiation" as described by ...
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Why is my aluminum foil emitting the same amount of infrared as the other objects in my room?
I got an infrared thermometer (SOVACARTE HS980E) recently and have been playing around with it.
My understanding is that it works by measuring the amount of infrared radiation coming off of the object,...
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What will happen if the inner walls of the perfect blackbody (shown in the image) is made perfectly reflecting?
I am curious about making the inner walls of this blackbody perfectly reflecting instead of perfectly absorbing.
If I keep on giving in incident radiation,the photon density inside will increase, ...
- 538
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Why solar flux concentrators can achive only $\rm 1500°C$ of temperature if Sun temperature is $\rm 5500°C$?
Why solar flux concentrators can achive only $\rm 1500°C$ of temperature if sun temperature is $\rm 5500°C$ ? If it is possible to concentrate a flux from a parabolic mirror of area $\rm 400\ m^2$ to ...
- 2,255
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When measuring IR for temperature of shiny surfaces, how is the object own emission added to the reflection?
While discussing measuring temperature of a heated glass plate used in 3D printers, it was pointed out that IR thermometers are not accurate because, for uncoated and shiny glass surface, they measure ...
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Can a pool of water be used to reflect heat from light?
I am designing a low impact house. I had planned to use a reflecting pool of water to increase the passive solar gain in the house in winter:
and reflect it away in the summer (note the structure on ...
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What colors reflects the most infrared radiation?
About fifteen years ago I read in a book (Physics by James Walker 3rd edition) that dark brown color reflects IR better than any other color and consequently weather heat since our bodies get most ...
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What causes materials like Vantablack to have their high optical absorption properties?
As per the title of this post. From reading, I understand that blackbody radiation is a factor I should consider here, with light being absorbed and converted to heat etc.
However, what I want to ...
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Black body radiation and why do we see different colors?
I am high school student and I am really confused about how black body radiation or radiation from any general body works?
Suppose we are observing the color of any body is green, does it mean that it ...
- 470
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Cavity Radiation, why should only standing waves persist in the cavity?
"Because when the box is in thermal equilibrium, there can never be any electric field at the walls for it would shake the charge in the wall around, changing the temperature, contradicting the ...
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Amount of heat emitted from the Sun by radiation
Supposing that the condition of humidity and the temperature are the same. Concretely if in one place on Earth there is the same humidity, temperature, it is more hot in the first part of the summer ...
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