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U-235 can fission by absorbing fast or slow neutrons, but it has a much larger cross section for slow ones, that is it absorbs slow neutrons much more readily than fast ones. This enables moderated reactors to operate with low enriched (5% or less) or even natural uranium, whilst fast reactors must have much more highly enriched uranium, ie with more U-235. The ultimate is the nuclear bomb, where almost pure U-235 will fission entirely with fast neutrons, if enough of it is suddenly put together.
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Is moderation of neutrons always used to slow nuclear fission?
No, moderation of neutrons is not always used to slow nuclear fission. In some types of nuclear reactors, such as fast breeder reactors, fast neutrons are intentionally not moderated to slow down the fission process. These reactors operate using fast neutrons to sustain a chain reaction. However, in most commercial nuclear reactors, moderation of neutrons is employed to slow down the fission process and maintain a controlled chain reaction.
What is the effect of slow neutron on nuclear reactions?
Slow neutrons are more likely to be absorbed by nuclei in nuclear reactions compared to fast neutrons. This absorption increases the probability of inducing fission in heavy nuclei or capturing the neutron to form a new isotope. Slow neutrons are commonly used in nuclear reactors to sustain and control nuclear fission reactions.
Why moderator is not used in case of fast breeder reactor?
Moderator is not used in case of fast breeder reactor because there is no need to slow down neutron energy. Nuclear fission takes place at high energy of neutrons.
What causes fission?
Only certain elements are fissionable, or at least with practical means. The fission of for example the atom U235 happens when it is struck by a slow neutron, it splits, which is fission, releasing two smaller atoms and two or three neutrons (products). The products from the nuclear reaction weigh less then the original atoms. The difference in weight is converted into energy.
Why fission cannot take place with fast neutron?
In order to cause an atomic nucleus to become unstable so that it will undergo fission, you have to add a neutron. If a slow neutron collides with an atomic nucleus, it will be absorbed into the nucleus and become part of it. The nuclear attraction of the nucleus is strong enough to grab a slow neutron. But a fast neutron cannot be captured because it has too much kinetic energy. The attraction of the nucleus is not enough to stop the motion of a fast neutron. Even if a fast neutron makes a direct hit on an atomic nucleus, it is just going to bounce off.
Why you use slow neutrons instead of fast neutrons in nuclear reaction?
in reacter U-235 fission is due to slow neutrons because in reacter the probability of fission from fast neutron is approximatly zero.
Is moderation of neutrons always used to slow nuclear fission?
No, moderation of neutrons is not always used to slow nuclear fission. In some types of nuclear reactors, such as fast breeder reactors, fast neutrons are intentionally not moderated to slow down the fission process. These reactors operate using fast neutrons to sustain a chain reaction. However, in most commercial nuclear reactors, moderation of neutrons is employed to slow down the fission process and maintain a controlled chain reaction.
Is uranium 238 a slow or fast neutron absorber?
uranium 238 is a fast neutron absorber the answer is correct but for more explanation:- when uranium 238 is bombard by neutron >>> uranium 238 , undergoes B decay>>>Np 239 ,undergoes B decay >>> Pu 239 finally undergoes alpha decay >>> fissile U
Why not fast neutron use in fission?
Because slow neutrons are the most efficient way to cause U235 to fission. The U235 nucleus is said to have a large cross section for the capture of slow neutrons, much larger than for fast neutrons.
What are the Specifications for uranium used in nuclear power plants?
The uranium is in the form of uranium dioxide, UO2, which is produced in small cylinders and assembled inside a zircaloy sealed sheath. The individual zircaloy tubes filled with uranium are then made up into a fuel assembly, the number in each assembly varies from one design to another. The uranium itself is enriched to about 4 percent U235. Natural uranium has about 0.7 percent U235, which is the isotope required for slow neutron fission.
What is the effect of slow neutron on nuclear reactions?
Slow neutrons are more likely to be absorbed by nuclei in nuclear reactions compared to fast neutrons. This absorption increases the probability of inducing fission in heavy nuclei or capturing the neutron to form a new isotope. Slow neutrons are commonly used in nuclear reactors to sustain and control nuclear fission reactions.
Is plodded a fast or a slow?
not a fast but slow
Why moderator is not used in case of fast breeder reactor?
Moderator is not used in case of fast breeder reactor because there is no need to slow down neutron energy. Nuclear fission takes place at high energy of neutrons.
The form of lullys french overture was?
slow-fast-slow (Apex)
What causes fission?
Only certain elements are fissionable, or at least with practical means. The fission of for example the atom U235 happens when it is struck by a slow neutron, it splits, which is fission, releasing two smaller atoms and two or three neutrons (products). The products from the nuclear reaction weigh less then the original atoms. The difference in weight is converted into energy.
Why fission cannot take place with fast neutron?
In order to cause an atomic nucleus to become unstable so that it will undergo fission, you have to add a neutron. If a slow neutron collides with an atomic nucleus, it will be absorbed into the nucleus and become part of it. The nuclear attraction of the nucleus is strong enough to grab a slow neutron. But a fast neutron cannot be captured because it has too much kinetic energy. The attraction of the nucleus is not enough to stop the motion of a fast neutron. Even if a fast neutron makes a direct hit on an atomic nucleus, it is just going to bounce off.
Do snowy owls produce fast or slow?
fast and slow
