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Why are high temperatures needed for fusion reactions to occur but not fission reactions to occur?
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What are fusion and fission with respect to nuclear physics?
Fission is a nuclear reaction where a heavy atom is split up into lighter elements, thereby producing energy. Fission is commonly used in nuclear power plants, but someday they will use fusion. Fusion is a nuclear reaction where very light elements are fused together under enormous heat and pressure into heavier elements, thereby producing energy. The Sun and all the stars are fusion reactors. Thermonuclear bombs (H-bombs) use fission (an A-bomb) to produce the heat needed for fusion.
What are the advantages of a fusion reactor compared to a fission reactor?
You must realise that any claimed advantages are based on scientists predictions, and to some extent wishful thinking, as it is not even determined in engineering terms how a nuclear fusion plant could be built, what materials could be used, and how the heat would be extracted. However ever since fusion was proposed, scientists have been pointing out that it would produce much less radioactivity than fission does, and this is true, there would not be the spent fuel containing very highly active fission products that fission produces. There would be activation of structures in the plant due to the neutron irradiation coming from the plasma undergoing fusion. There are also consequences from needing to produce the tritium fuel, which is a dangerous substance to human health. So it all depends on future progress with ITER and further test rigs, but at the moment it is academic since it is very unlikely to happen within this century.
What is the source of energy in nuclear power plants?
The source of energy in almost all nuclear power plants is fission or the splitting of the atom. There are a few experimental fusion power plants, (or the joining of the atoms), but, there are few of them, since the energy needed to produce fusion is extremly high, and only last a few seconds. Around 99.99% of nuclear power plants are fission power plants.
Do fusion bombs leave a trail of nuclear radiation like a fission bomb after they explode?
Great question, nicely worded except I'm not sure what you mean be "trail". If by "trail" you mean windblown fallout plume, then yes and usually much bigger because their yield is bigger. Even though a fusion bomb is called a fusion bomb, the standard design generates about 90% of its yield from fission because the high energy fusion neutrons make the depleted uranium tamper fission, which also generates most of the bomb's fallout. In the 1956 Redwing series in the pacific, the US tested the world's first "clean" fusion bombs at Bikini atoll; 2 devices, 1 of which had as little as 5% of its yield from fission most of which was believed to be due to the fission trigger and the rest the fission "sparkplug". This reduced fallout dramatically, though the yield was also reduced and more lithium-deutride fuel was needed making the "clean" bomb more expensive than a standard one.
Why do you use fission reactors not fusion reactors?
No way has yet been found to reach break-even in a controlled fusion reaction and get as much energy out as was needed to put in to start the reaction. To make a reactor you need to go past break-even and release extra energy.
Do fusion reactions provide nuclear power?
No, a fission reaction is not necessary to trigger a fusion reaction, but for us on earth, it is. In the field of nuclear weapons, a fission bomb is needed to create the heat necessary to set off a fusion weapon. We have to use fission, or, rather, the energy created by that, to initiate the fusion reaction. It might be possible to use a high power source, like a laser, on a small amount of material to get fusion to occur. But we are still experimenting with this in the Tokamak, and it's far from being a done deal. Stars are, in general, massive nuclear fusion reactors. Their constant consumption of fuel powering their high rate of fusion creates a massive amount of energy, and the stars' huge gravity keeps this process from blowing the whole thing apart. No fission is needed to sustain this reaction.
How did the atomic bomb become outdated?
The fission bomb never became outdated, one is needed in every single fusion bomb as the primary to set off the fusion reaction.
Compare nuclear fission and nuclear fusion?
Nuclear fusion is the process of squeezing two lighter atoms together to make heavier atoms; nuclear fission is the process of splitting heavier atoms into lighter ones. In both processes, some of the mass of the original atoms are converted into energy; fusion tends to convert more mass into energy than fission does, so fusion tends to create more energy. Heavier atoms needed for a fission chain reaction tend to be unstable and radioactive, and thus the fission process tends to produce more radioactivity.
What are fusion and fission with respect to nuclear physics?
Fission is a nuclear reaction where a heavy atom is split up into lighter elements, thereby producing energy. Fission is commonly used in nuclear power plants, but someday they will use fusion. Fusion is a nuclear reaction where very light elements are fused together under enormous heat and pressure into heavier elements, thereby producing energy. The Sun and all the stars are fusion reactors. Thermonuclear bombs (H-bombs) use fission (an A-bomb) to produce the heat needed for fusion.
What element is needed to make a nuclear weapon?
Uranium makes for an excellent element for nuclear fission. Hydrogen is most commonly used for nuclear fusion.
Why is a fission bomb needed as part of an hydrogen bomb?
Yes, in two or three places depending on the design used:the atomic fission bomb primarythe plutonium sparkplug rod that runs through the center for the length of the secondaryif present the uranium tamper that surrounds the secondary inside the hohlraum, if a material other than uranium (e.g. lead, tungsten) is used for the tamper then no fission happens in itIf additional stages (e.g. tertiary, quaternary,...) are present in the design, repeat numbers 2 and 3 for each additional stage to get all the places that fission is used.
Why is hydrogen bomb more powerful and destructive than the atom bomb?
The term atom bomb is somewhat ambiguous. The more precise distinction that you are trying to make is between a fission (or uranium or plutonium based) bomb and a fusion (or hydrogen based) bomb. The process of nuclear fission releases a certain amount of energy, and the process of nuclear fusion, per nucleus, releases a much larger amount of energy. Hence, you can build much bigger bombs based on fusion (although they still contain fission bombs which are required to create the high temperature needed for fusion).
How is a nuclear fusion the same as a chemical reaction?
They are...reactions and can lead to new elements; but the big difference is that a nuclear fusion involve particles from the atomic nucleus and a very great energy is needed.
What is the different between nuclear fusion and nuclear fission?
Difference between fusion and fissionNuclear fusion is taking two atoms and combining them in to one atom, while nuclear fission takes one atom and splits it into two atoms.Both reactions involve the nucleus of an atom, and in both reactions, lots and lots of energy are released. Other than that, the two reactions are pretty much opposite. Fission involves the splitting of an atomic nucleus. Fusion involves the fusing of two or more units to create a new, heavier nucleus.Links are provided to articles on both subjects that have been posted by our friends at Wikipedia, where knowledge is free.In nuclear fusion two lighter nuclides fuse (join together) to form a heavier nuclide.In nuclear fission one heavy nuclide splits into two smaller ones. These two are not necessarily identical.Nuclear fission releases energy only if the resulting nuclides are as heavy as or heavier than Iron40.Fusion releases energy only if the resulting nuclide is as light as or lighter than Iron40.It is possible to make elements heavier than Iron40 by fusion, but these reactions are strongly endothermic ( which means that a great deal of energy must be supplied from an external source). This can be done in an accelerator, but the process takes place in any quantity only in an exploding star.Nuclear fission is when a large nucleus such as uranium or plutonium splits into two smaller nuclei. When Uranium with an atomic mass of 235 absorbs a neutron and becomes Uranium 236 (its critical mass) it splits into two nuclei releasing loads of energy.Nuclear fusion is when two small nuclei (smaller the iron) fuse together to make a bigger one. The high energies and pressures are needed are very hard to recreate on earth because if you think about it the sun is hot because nuclear fusion is happening inside so we have to create the sun on earth. The only place fusion can happen naturally in stars. Fusion releases even more energy than fission. Most fusion happens between two hydrogen atoms to make a helium atom.Deuterium is hydrogen with one proton and one neutron (normal hydrogen is 1 proton only). Tritium is Hydrogen with two neutrons and one proton. These particles are what form hydrogen. If you add up the number of particles you will notice that one neutron is left over in the making of helium. This is turned into the massive amount of energy released in a fussion reaction and relased as light but mostly heat.Nuclear fision is the splitting of atoms and fusion is the combining of atoms
How does a fusion reactor work?
Fusion energy is created when nuclei are forced (or fused) together. . Nuclei, in the form of a thin gas, are magnetically suspended and heated to 150 million° C in a donut shaped vacuum chamber. The nuclei snap together giving off energy and helium. . Fusion (fusing nuclei) should not be confused with fission (splitting nuclei). Both processes utilize the strong nuclear force to produce energy but have significant differences. Two most prominent differences are ready to use technology (fission wins on that point,) and environmental safety (fusion has next to no radioactive waste or risk of melt-down). . Some fusion systems promise to produce energy without steam turbines, generators, cooling towers, and other energy sapping devices that must be used with coal burning and fission power stations. But to accomplish this fuels such as the rare helium-3 at still hotter operating temperatures are needed.
What are the advantages of a fusion reactor compared to a fission reactor?
You must realise that any claimed advantages are based on scientists predictions, and to some extent wishful thinking, as it is not even determined in engineering terms how a nuclear fusion plant could be built, what materials could be used, and how the heat would be extracted. However ever since fusion was proposed, scientists have been pointing out that it would produce much less radioactivity than fission does, and this is true, there would not be the spent fuel containing very highly active fission products that fission produces. There would be activation of structures in the plant due to the neutron irradiation coming from the plasma undergoing fusion. There are also consequences from needing to produce the tritium fuel, which is a dangerous substance to human health. So it all depends on future progress with ITER and further test rigs, but at the moment it is academic since it is very unlikely to happen within this century.
What is one example of a place where naturally occurring extreme temperatures provide the energy needed to bring hydrogen nuclei together in a fusion reaction?
stars such as our sun
