Questions tagged [radiation]
Radiation is a process in which energetic particles or energetic waves travel through a medium or space. The particles or waves radiate (i.e., travel outward in all directions) from a source.
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Regarding the absorption property of a blackbody
Consider a blackbody of surface area $S_b$ and at temperature $T_b$. It is placed inside an evacuated chamber (to neglect all the effects of convection), with walls of chamber at temperature $T_c$ and ...
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If a proton transforms into a neutron by releasing a positron why should this process create more mass? [duplicate]
If waves can interfere and thats why cancel out or add up why we cannot think the same about the natterial feature called mass as in this explained example in the title of this posted question??Thanks ...
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What are some highly unstable phenomena you can observe from lightyears away?
I'm currently drafting some scifi story where the protagonist is in a long timeloop and wants to figure out when the loop starts exactly based on observing some unstable phenomena, like atomic decay ...
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Neutron diffusion equation cylinder question
Hi there I was wondering if anyone could help me with how to approach this problem that I have. I'm looking to find the neutron flux outside of a cylindrical container which is made of steel, however ...
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Does the Host Rock of This Mexican Hyalite Show Signs of Uranium Minerals? I Previously Cut It and Am Now Concerned
I previously cut a Hyalite specimen from Zacatecas, Mexico. Using a Geiger counter, I measured a slightly higher level of radioactivity on the cut surface compared to the environment. Although I know ...
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Y90 and Sr90 beta emissions have the same ranges but different average energies?
Why does Y90 and Sr90 beta emissions have the same range in air if they have different energy averages (0.935 MeV, 0.196 MeV, espectively)? I would assume that their average energy would indicate ...
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Is the generation of NMR signal due to spontaneous emission?
The usual description of how NMR signal is generated is that the sample has some equilibrium magnetisation along the $z$ axis, this is then flipped into the $x$-$y$ plane by a 90° pulse and there it ...
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Why are zirconium pressure tubes stored in waste containers when removed from nuclear plants?
Hi this is probably a bit of a silly question but I've been thinking a lot about the use of zirconium in nuclear plants. I know that zirconium has a very low neutron absorption cross section and that'...
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Which exact element makes Spent Nuclear Fuel dangerous?
I understand that beta and gamma emissions are what makes the decay of a radioisotope dangerous. However, U-238, which is what SNF is mostly made of, doesn't emit gamma or beta particles frequently ...
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How to calculate mean energy of fluorine-18 positron?
I know that Fluorine-18 becomes stable when a neutron takes the place of a proton and becomes Oxygen-18 where a positron and nutrino are emitted.
Using Einstein formula, I can find the maximum energy (...
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Do alpha and beta particles have the same energy regardless of its source?
The dangers of nuclear radiation are often described in terms of its penetration power. For instance, alpha particles can be blocked by a sheet of paper, whereas gamma can be stopped by a thick piece ...
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What happens to the electric field in an accelerated capacitor?
Say we have a charged capacitor with some charge $Q$ in one of its plates (and of course the opposite charge on the other plate). It is a well-known result that the electric field inside this ...
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Geiger-Nuttall law alternative form
I've seen the two forms of Geiger-Nuttall law. which is the
$$log\;\omega = aE^{1/2} + b\hspace{5em}:(1)$$ and $$log\;\omega=a'logR_{\alpha}+b'\hspace{4em}:(2)$$
From the range-energy relation, we ...
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Why does a heated body emit a continuous spectrum of waves, while a burning body emits one color?
Why does a heated body emit a continuous spectrum of waves (as I understand it, that's why they burn red/white/blue), and a burning body is one color?
as I understood it, for example, the green flame ...
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Demonstration of constant radiance for Lambertian Surfaces
I'm approaching to radiometry and I'm struggling with one of the properties of Lambertian surfaces.
We know that the radiance is the radiant flux emitted, reflected, transmitted or received by a ...
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