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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What is the input of calculating signal noise ratio (SNR) and detective quantum efficiency (DQE) in estimation of imaging system?
In its definition, the signal noise ratio (SNR) is the ratio of the mean siganl to the standard deviation of the noise. However, for a given picture what is the noise? The detective quantum efficiency ...
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My ionizing smoke detector fell a month ago. Is it possible I've been irradiated? [closed]
My ionizing smoke detector is from Kidd, it's written it produces 0.6 microCuries in nominal conditions but a) It's expired since 2010 (I'm renting, just realised this), and b) It fell out of nowhere ...
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Need help with SMRs and nuclear reactors [closed]
I'm writing my IB extended essay on SMRs and how they might be useful for energy generation in Singapore but I don't quite understand a couple things.
How do their passive safety systems work and ...
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How well does a cavity with a hole approximate a black body?
Cavity with a hole is a frequently cited approximation to a black body (more precisely, it is the hole that is the black body here):
Is there a simple estimate of how well such a cavity approximates ...
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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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Why n+ contact of p type Ge is 700um thick compared to p+ contact of n type Ge only 0.3um?
Whether the reason is as follows?
Predominantly HPGe is p type. So compensation of large p type impurity requires more n+ contact. (700um)
But n type Ge is made by doping of excess addition of n type ...
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A charged particle, a magnetic field and the particle's path
Quoted below is a question & the provided answer:
Question:
Describe the path of the $\alpha$ particles in the space between the
magnetic poles.
Answer:
curved path stated or drawn
path at ...
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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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Is there heat transfer through radiation in a drinking flask with styrofoam insulation?
Suppose we have a drinking flask with styrofoam between outer and inner walls. The heat can be transferred through styrofoam by conduction. Is the heat transferred by radiation as well?
My lecturer ...
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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 there anything that can produce light without UV rays?
I've read that everything from fire to LEDs can produce UV radiation. Generally, unless intended otherwise, lightbulbs will have a phosphor coating to prevent UV radiation from escaping the bulb. ...
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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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