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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.

In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. Two types of radiation are commonly differentiated in the way they interact with normal chemical matter: ionizing and non-ionizing radiation. The word radiation is often colloquially used in reference to ionizing radiation (i.e., radiation having sufficient energy to ionize an atom), but the term radiation may correctly also refer to non-ionizing radiation (e.g., radio waves, heat or visible light). The particles or waves radiate (i.e., travel outward in all directions) from a source. This aspect leads to a system of measurements and physical units that are applicable to all types of radiation.

Source: http://en.wikipedia.org/w/index.php?title=Radiation&oldid=492776012

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$\beta^+$ decay

We've been discussing radioactive decay at school, and I grasped everything except for $\beta +$ decay. When I googled radioactive decay, I immediately found out they dumbed down radioactive decay for us, which is probably why they didn't care to…
Radio
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What does a reading of $12000$ Roentgen mean?

In the HBO series Chernobyl they frequently cite Roentgen readings, such as the 3.6 maximum reading on their initial dosimeters, the 15,000 on the meter on the front of the truck driven as close as possible to the damaged reactor, and 12,000 on the…
Jason Goemaat
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What common materials can effectively block infrared radiation?

I have a plastic container and want to make sure that infrared radiation (specifically, in the 750-850 nanometer range) cannot pass through it. Would wrapping it in aluminum foil do the trick? If not, what household material would be best? The…
John
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Where does the excess energy emitted by a microwave go?

If there is nothing in the microwave, where does the excess radiation go? Why doesn't the radiation accumulate and blow it up? Should I cook two pieces of Canadian Bacon twice as long as I cook one?
user420667
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Does thorium-232 emit X-rays?

The question is derived from an experiment... "Red" tungsten TIG welding electrodes consists 2% of thorium-232. They are slightly radioactive... I have such electrodes, so I checked their radioactivity by an NR-750 Geiger counter (indeed they are…
Andrew123
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Are these radioactive particle matter and air emmissions dangerous, 2000KM from Fukushima?

I have 2 questions, as a expat and new parent residing in Shanghai (2000km from Fukushima) where we are now experiencing radioactive fallout from the Fukushima Nuclear Plant (Japan), we can not get any 'real' infomation about what are safe limits…
user3001
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Can the 7-10 rule of thumb for radiation be understood theoretically?

Is there a way to understand where the 7-10 Rule of Thumb for nuclear radiation comes from? A seven fold increase in time after explosion results in a 10 fold reduction in exposure rate. From a FEMA page on responding to "nuclear threats": From…
BMS
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continuous and line spectra during beta and alpha particle emission

What is the reason behind alpha particle giving line spectra and beta particle giving continuous spectra? (To notify this question had already been asked on this site. Yet, I am not quite clear with its explanation. I wish someone could answer it…
user63923
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Without a reactor vessel breach, how does radiation build-up in containment buildings of troubled nuclear reactors?

It seems that at Three Mile Island and in Fukushima, there was a build-up of radioactive gasses, and other gasses like hydrogen in the containment buildings. Wikipedia says: The containment [building] is the fourth and final barrier to radioactive…
Louis Waweru
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Per unit of energy, what radiation is the most penetrating?

This question about nuclear reactor shielding got me wondering, what forms of radiation are the hardest to shield? I suppose Neutrinos will have to be excluded since they're the obvious winner. So assuming an equal kinetic energy, what's the…
Brandon Enright
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Radiation: Inverse square law

Gamma radiation follows the inverse square law, I understand this as "double the distance, quarter the intensity" So if you have a gamma source, at the source (distance = 0), the Intensity is $I_0$, and say at distance = 1, the Intensity is…
Jonathan.
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Cloud chamber shows initial rain effect but no tracks

I am trying to make a cloud chamber but it does not work yet. I do see a rain effect at the beginning which means that the alcohol is condensing and the rain effect slowly disappears as the vapor gets more saturated. But after that I do not see any…
TheCodeGoat
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Is a beta decay possible with out the emission of an electron in the process?

Is a beta decay possible with out the emission of an electron in the process ? Beta decay involves the formation of a proton and an electron from a neutron.
HOLYBIBLETHE
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Radiation absorption and resultant temperature rise

I have a doubt about radiation absorption and temperature increase. I was taught that the larger heat capacity of diatomic molecules over monoatomic molecules is the result of the possibility that the diatomic molecules may absorb some photon and…
user3113647
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Can a free hydrogen atom constitute ionizing radiation?

Radiation is basically just particles flying around, right? Are free hydrogen atoms just typically not moving fast enough to be considered "radiation"?
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