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In a nuclear reactor the moderator is usually made of graphite placed between the fuel rods used to slow down neutrons all of the above none of the above?
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Are graphite rods radioactive?
no graphite rod not radioactive but these r absorb radioemission rays that's why people think so because in the nuclear plant graphite rod use as a controling nuclear reaction by absirb the nuclear emission rays .A2. The graphite is used as a Moderator - a material that slows the neutrons down sufficiently that they have a greater chance of collision and thus releasing some of their energy. Which we use as thermal energy.Otherwise, the neutrons would have only a small chance of interacting - they are travelling very fast, and the dimensions of a nuclear pile is only a metre or so in dimension. Having interacted to give up some of their energy, the neutrons then just lose the remainder of their energy in the shielding.
Why is graphite used as a moderator in some nuclear reactors?
It is used as a moderator. Natural uranium will not undergo nuclear fission by itself because neutrons emitted by fissioning U-235 tend to be absorbed by U-238. However, if the neutrons can be slowed down, it turns out that U-238 is less likely to eat them, and enough are available to fission U-235 and keep the reaction going. Graphite has the useful property that it can slow neutrons down without eating them, so if you embed uranium lumps in a graphite matrix with appropriate spacing, the neutrons which get into the graphite will be slowed down, and when they finally hit a lump of uranium they are likely to be taken up by U-235 and cause fission.Any light element with a sufficient distaste for neutrons can be used as a moderator. Heavy water (deuterium oxide) works nicely. Natural water has slightly too high an appetite for neutrons to work well, but if the concentration of U-235 is raised a bit, you can make a reactor with natural water moderator. That is how power reactors work in the USA and most other countries.
What 3 words holds protons and neutrons together in the nucleus?
The force between nucleons is called nuclear force.
How do protons and neutrons hold an atom together?
The Strong nuclear force is what holds the protons and neutrons together in an atoms nucleus. Think of a gorilla with an atom of two protons and two neutrons together and his hands holding the atoms together.
What are nuclear bombs made out of?
plutonium and neutrons
Why is the moderator important in a nuclear reactor?
The moderator is used to slow down the neutrons present in the core of the reactor. Normally the neutrons produced as the nuclear fuel (e.g. uranium) is fissioned are travelling too fast to produce a sustained chain reaction. Some examples of moderators are cadmium, heavy water and graphite.
Are control rods in nuclear reactors made of graphite?
No, control rods in nuclear reactors are not made of graphite. The control rods have to be able to gather up the neutrons to shut the reactor down, so boron is often selected. Graphite is used in some reactors as a moderator, and a moderator slows down neutrons. The slower neutrons have a greater ability to undergo neutron capture to continue the chain.
What is a moderator when it concerns nuclear energy?
A moderator is a material that slows fast neutrons.
Slows down neutrons in a nuclear reactor?
moderator
Which is used as moderator in nuclear reactor?
Most often, light water (H2O) is used as a moderator in a nuclear reactor. Sometimes, heavy water (D2O), or graphite is used.
Do moderator in nuclear reactor slows down the neutrons emitted during fission?
Yes, it is the main moderator function in what is called "thermal nuclear reactors"
Which material is used as a moderator in nuclear power plant?
It can be light water, heavy water, or graphite
How much graphite is used in a nuclear power plant per year?
United States nuclear power plants do not use graphite for operation and thus the answer is "none". Graphite is used in some reactor designs as a "moderator", which is the reactor feature that slows down neutrons so that the chain reaction will continue. US nuclear plants are "light water reactors" which means that they use regular water as the moderator. Canadian plants, for example, are "heavy water" plants which use duterium as a moderator. Chernobyl, the Ukranian plant that exploded in the 1980's, used graphite as a moderator.
Are graphite rods radioactive?
no graphite rod not radioactive but these r absorb radioemission rays that's why people think so because in the nuclear plant graphite rod use as a controling nuclear reaction by absirb the nuclear emission rays .A2. The graphite is used as a Moderator - a material that slows the neutrons down sufficiently that they have a greater chance of collision and thus releasing some of their energy. Which we use as thermal energy.Otherwise, the neutrons would have only a small chance of interacting - they are travelling very fast, and the dimensions of a nuclear pile is only a metre or so in dimension. Having interacted to give up some of their energy, the neutrons then just lose the remainder of their energy in the shielding.
Why is graphite used as a moderator in some nuclear reactors?
It is used as a moderator. Natural uranium will not undergo nuclear fission by itself because neutrons emitted by fissioning U-235 tend to be absorbed by U-238. However, if the neutrons can be slowed down, it turns out that U-238 is less likely to eat them, and enough are available to fission U-235 and keep the reaction going. Graphite has the useful property that it can slow neutrons down without eating them, so if you embed uranium lumps in a graphite matrix with appropriate spacing, the neutrons which get into the graphite will be slowed down, and when they finally hit a lump of uranium they are likely to be taken up by U-235 and cause fission.Any light element with a sufficient distaste for neutrons can be used as a moderator. Heavy water (deuterium oxide) works nicely. Natural water has slightly too high an appetite for neutrons to work well, but if the concentration of U-235 is raised a bit, you can make a reactor with natural water moderator. That is how power reactors work in the USA and most other countries.
What is the moderator in US nuclear power plants?
Neutrons released from the fissioning, or splitting, of Uranium or Plutonium atoms collide with the molecules of the moderator, losing some of their energy in the process. This slows the neutrons down (slow neutrons are referred to as "thermal" neutrons") so that they are more likely to cause fission when colliding with another Uranium or Plutonium atom. In the most common types of reactors the moderator used is ordinary distilled water which is also used as the coolant for the reactor. Graphite and heavy water can also be used, and there are types of reactors which use no moderator at all - they operate on "fast" neutrons alone.
In a nuclear reactor why does the moderator need to slow down the neutrons?
Nuclear fission of Uranium-235 is more efficient when hit by neutrons with low energy of the order of electron volts. However, neutrons coming from fission are at high energies around 2 megaelectron volt. Accordingly, the moderator is needed to slow down the neutrons coming from fission to low energy values through scattering process with moderator molecules. This is the concept of the so called "thermal nuclear reactors"
