The property of some materials by which individual atoms decay, emitting energy or particles often transforming into different elements in the process.
Questions tagged [radioactivity]
717 questions
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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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How do we know that radioactive decay rates are constant over billions of years?
A friend and I recently discussed the idea that radioactive decay rates are constant over geological times, something upon which dating methods are based.
A large number of experiments seem to have shown that decay rate is largely uninfluenced by…
Pertinax
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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 technetium unstable?
Is there a simple account of why technetium is unstable?
From the Isotopes section of Wikipedia's article on Technetium:
Technetium, with atomic number (denoted Z) 43, is the lowest-numbered element in the periodic table that is exclusively…
Niel de Beaudrap
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Can 1 kilogram of radioactive material with half life of 5 years just decay in the next minute?
I wondered this since my teacher told us about half life of radioactive materials back in school. It seems intuitive to me to think this way, but I wonder if there's a deeper explanation which proves me wrong.
When many atoms are involved, half life…
uylmz
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6 answers
Why does the same proportion of a radioactive substance decay per time period? (half life)
Just wondering, if decay is random, why does the activity half every half life, as in, why does it have to reduce by the same proportion in the same time period?
Saharsh Aanand
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Can radioactivity be slowed through time dilation?
Can radioactivity be slowed using the effect of time dilation?
If you put cesium, tritium or uranium in a cyclotron at relativisitic speeds, do their half lives become longer in our frame?
Could this be used as a means to store radioactive material?
Michael
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How does the Earth's center produce heat?
In my understanding, the center of the Earth is hot because of the weight of the its own matter being crushed in on itself because of gravity. We can use water to collect this heat from the Earth and produce electricity with turbines. However, I'd…
rydwolf
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Can a radioactive atom be prevented from decaying if it's in a REALLY strong chemical bond?
So, based on this question, a molecule containing a radioactive atom will break when the atom decays. But suppose you need a lot energy to break the compound apart --- as in, more energy than the decay of the atom will release (obviously, a molecule…
Palbitt
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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)…
Luke B
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In nuclear physics, what length year in seconds is used?
So I'm working on a nuclear physics problem and am looking at radioactive decay. The common unit used for very long decays is years within the literature. Is this the sidereal or tropical year? I want to use units of seconds but seeing as how these…
RocketTwitch
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What is the decay width and why is it given in energy units?
I'm reading Thomson, Modern Particle Physics, and in chapter 16 author says that the decay width of the Z boson is $\Gamma_Z =2.452 \pm 0.0023 \,\mathrm{GeV}$. He also says the total width of the decay is the sum of the partial widths,…
Patrick
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Is it possible that every single isotope is radioactive, and isotopes which we call stable are actually unstable but have an extremely long half-life?
I've read that tellurium-128 has an half-life of $2.2 \times 10^{24}$ years, much bigger than the age of the universe.
So I've thought that maybe every single isotope of every single atom are radioactive, and isotopes which we call "stable" are…
Quantum Force
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Why exactly do atomic bombs explode?
In atomic bombs, nuclear reactions provide the energy of the explosion. In every reaction, a thermal neutron reaches a plutonium or a uranium nucleus, a fission reaction takes place, and two or three neutrons and $\gamma$ radiation are produced. I…
L.Gyula
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Does the halflife time of a radioactive material decrease if its temperature increases?
If at high temperatures atoms are more intensely interacting with each other or emitted photons that also could make the core vibrate. Is in these circumstances the radioactive material more likely to fission faster? Can this be used to get rid of…
Krešimir Bradvica
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