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

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Why is my dryer radioactive?

My Geiger counter measures a background radiation level in my home of 0.09–0.11 μSv/h. When I stick it inside the dryer right after it finishes a cycle (while the clothes are still inside), it registers a radiation level of 0.16–0.18 μSv/h. What…
Marsroverr
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Why is nuclear waste more dangerous than the original nuclear fuel?

I know the spent fuel is still radioactive. But it has to be more stable than what was put in and thus safer than the uranium that we started with. That is to say, is storage of the waste such a big deal? If I mine the uranium, use it, and then bury…
Anthony B
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Why can Hiroshima be inhabited when Chernobyl cannot?

There was an atomic bomb dropped in Hiroshima, but today there are residents in Hiroshima. However, in Chernobyl, where there was a nuclear reactor meltdown, there are no residents living today (or very few). What made the difference?
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How does an ordinary object become radioactive?

In the 2019 miniseries "Chernobyl", ordinary objects are depicted as being capable of becoming radioactive, such as clothes, water, stones. How exactly does something composed of a non-radioactive mass, become radioactive? I'm aware of the…
AlphaCentauri
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Why is radioactive half-life constant?

Say you have just four radioactive atoms with a half-life of one hour. (I am using a small number of atoms to keep it simple and illustrate my confusion more clearly). So that means one hour from now, two of the atoms will have decayed (on average)…
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Do nuclei emit photons?

Generally in text books they say that when a electron goes from high energy state to a lower energy state it emits photons. My question is, it is possible that a proton that goes from high energy state to a lower energy state emits photons too?
amilton moreira
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The problem of self-force on point charges

Allow me to preface this by stating that I am a high school student interested in physics and self-studying using a variety of resources, both on- and off-line, primarily GSU's HyperPhysics website, Halliday & Resnick's Fundamentals of Physics,…
obataku
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How is Alpha Radiation possible?

Alpha radiation would seem to occur when a pair of protons and neutrons are magically plucked from the amorphous (i.e. having no particular structure) nucleus of a heavier atom. Some of the problems associated with this approach, but which are…
Excentrix
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What is wrong with my setup of cloud chamber?

My setup: plastic box (~1l) with the cover painted black mat the bottom of the box covered with sponges saturated with ethyl alcohol (90%) to the limit (all over sponge capacity poured back to bottle) turned upside down and placed on ~0.5kg of dry…
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Is a suit that hides a soldier's heat signature fundamentally possible?

I recently played "Crysis", a game where the protagonist wears a suit that allows the player to hide both himself and his heat signature. Then I watched Iron Man 3, where a kid suggests that Tony Stark should have implemented retro reflection panels…
J.Todd
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Is it safe to keep uranium ore in my house?

I bought 5.6 gr of uranium ore. The measured gamma radiation is 1µSv/h, we didn't have the instruments to measure alpha/beta radiation. EDIT: The gamma radiation was measured at 1cm distance. I also updated the unit of measurement as I had only…
Gello
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Decay of massless particles

We don't normally consider the possibility that massless particles could undergo radioactive decay. There are elementary arguments that make it sound implausible. (A bunch of the following is summarized from Fiore 1996. Most of the rest, except as…
user4552
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What exactly is the difference between radiation, conduction, and convection?

Okay, so everywhere I've read, I hear the main difference is the requirement of a medium. But for example, if you take the case of heat 'radiating' from a red-hot iron, isn't that actually convection and not radiation? I mean, isn't the temperature…
sciencerocks
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Why are alpha particles such a prominent form of radiation and not other types of nucleon arrangement?

It is said in many textbooks that alpha decay involves emitting alpha particles, which are very stable. Indeed, the binding energy (~28.3 MeV) is higher than for $Z$-neighboring stable isotopes. But the binding energy is lower than, for example,…
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Why is the graphite moderator in a nuclear reactor radioactive?

Some nuclear reactors (like the RBMK in Chernobyl) use graphite as a neutron moderator. As far as I understand, this graphite material, either in rods or as blocks with embedded channels, surrounds the uranium fuel rods and is used to moderate the…
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