The fusion tag is used for questions about nuclear fusion, both the basic process at a physical level and it's use as a potential energy source.
Questions tagged [fusion]
702 questions
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Why do fusion and fission both release energy?
I only have high school physics knowledge, but here is my understanding:
Fusion: 2 atoms come together to form a new atom. This process releases the energy keeping them apart, and is very energetic. Like the sun!
Fission: Something fast (like an…
user230910
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Would a pin head heated to 15 million degrees Celsius kill everyone in a 1000 mile radius?
The YouTube video How Hot Can it Get? contains, at the 2:33 mark, the following claim:
A pin head heated to 15 million degrees will kill everyone in a 1000 miles radius.
On what basis can this claim be true?
Some of the things I can think…
Jus12
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Why didn't the Big Bang create heavy elements?
In the case of a supernova explosion it is possible to create heavy elements through fusion. Supernovae have a tremendous amount of energy in a very small volume but not as much energy per volume as there was in our early universe. So, what is the…
Alex
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Why isn’t CERN afraid of a fusion reaction in the LHC?
Given that they can reach terrifying energies and temperatures, why isn’t fusion of protons a concern? After all, they start with a plasma and ram protons into each other.
At some point the strong force will overcome the proton-proton electric…
aquagremlin
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Can Jupiter be ignited?
Our solar system itself contains two candidate "Earths"
One is Jupiter's moon Europa and another is Saturn's moon Titan. Both of them have the problem of having at low temperature as Sun's heat cannot reach them.
Jupiter is made up mostly of…
Xinus
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9 answers
Why doesn't the nuclear fusion in a star make it explode?
I have a rather naive question. In stars such as the Sun, what prevents the whole thing exploding at once? Why is the nuclear fusion happening slowly? I can only assume that something about the fusion is fighting the gravity and slowing the fusion…
sku
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What is the origin of elements heavier than iron?
In all the discussions about how the heavy elements in the universe are forged in the guts of stars and especially during a star's death, I usually hear that once the star begins fusing lighter atoms to produce iron (Fe) that's the end of the star's…
Zubin
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What stops us from creating a nuclear fusion reactor as we already have the hydrogen bomb working on the same principle of fusion?
I have been out of physics for some time now since my childhood, so please bear with me if the question below feels too novice.
I grew up with the understanding that the nuclear fusion reaction is still a dream of many people as it's a source of…
Xinus
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Nuclear Fusion: Why is spherical magnetic confinement not used instead of tokamaks in nuclear fusion?
In nuclear fusion, the goal is to create and sustain (usually with magnetic fields) a high-temperature and high-pressure environment enough to output more energy than put in.
Tokamaks (donut shape) have been the topology of choice for many years.…
Valentina
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Using nuclear devices to terraform Mars: Elon Musk's nuclear proposal?
Elon Musk has recently suggested Using nuclear devices to terraform Mars. In the past, comet related ideas were mooted, but Musk seems, to me anyway, to be a man in a hurry and perhaps his idea has some merit, as waiting around for suitable comets…
user81619
30
votes
3 answers
Why is the nucleus of an Iron atom so stable?
Lighter nuclei liberate energy when undergoing fusion, heavier nuclei when undergoing fission.
What is it about the nucleus of an Iron atom that makes it so stable?
Alternatively: Iron has the greatest nuclear binding energy - but why?
martin clayton
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27
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Why don't deuterons produce a helium-4 nucleus when they fuse?
I would expect two deuterium nuclei to fuse straight into a single helium-4 nucleus, because that's by far the most stable way to arrange 2 protons and 2 neutrons. But instead, any two fusing deuterons have a 50-50 chance of producing either a…
zucculent
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Why can't hydrogen and helium fuse?
In the hearts of stars, hydrogen atoms fuse together to make helium. After the hydrogen in the core is depleted, the star changes state and conditions at the heart of the star make it possible for helium atoms to fuse together.
There are parts of a…
usernumber
- 467
26
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1 answer
Why is a stellarator-type nuclear fusion reactor so oddly-shaped?
My first impression: It's a mess.
Why is it shaped like that? I can't find any info about its shape other than it's a special arrangement of magnetic coils.
Aloha
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When did the first carbon nucleus in the Universe come into existence?
I am a chemist with a passion for astrophysics and particle physics, and one of the most marvellous things I have learned in my life is the process of stellar nucleosynthesis. It saddens me how my colleagues point to the periodic table and draw…
