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Neutrons in a nuclear fission chain reaction must be controlled for two reasons...
First, they must be moderated, or "slowed down", to exactly the right level of energy required to sustain the reaction. This is because, initially, the neutrons are too fast to sustain the fission reaction. They must be slowed down, but not too much, otherwise the reaction will stop.
Second, they must be controlled. You want the reaction to proceed at an orderly pace, at a constant rate. To do this, you need, on a statistical average, exactly one neutron to go on to fission one atom to produce one parcel of binding energy release and one neutron, to repeat without multiplying or dividing. This is what we call KEffective = 1, where the rate of reaction does not change.
Moderation and control. In tight balance. Easily upset. Fortunately, when upset, the tendency is to shutdown. That is engineering safety.
Neutrons in a chain reaction must be controlled to prevent the reaction from reaching a critical mass and becoming uncontrollable. By controlling the rate of neutron production and absorption, engineers can manage the reaction to ensure it remains stable and does not lead to a runaway nuclear event.
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What must happen for nuclear reactor to make electricity?
a chain reaction
A nucleus captures two neutrons and decays to produce one neutron is this process likely to produce a chain reaction?
Yes, if the nucleus is undergoing fission and releasing additional neutrons upon decay, capturing two neutrons could contribute to a chain reaction by generating more fission events and more neutrons. However, the likelihood of a chain reaction occurring also depends on the specific nucleus involved and the surrounding conditions.
What must metal fuel rods inside a nuclear reactor be bombarded with in order to start a chain reaction?
The metal fuel rods inside a nuclear reactor must be bombarded with neutrons in order to start a chain reaction. This process triggers the fission of uranium atoms in the fuel rods, releasing energy in the form of heat.
For a fission reaction to fail to be maintained as a chain reaction each fission must produce less than additional fission reaction(s).?
In a continuous chain reaction at a steady rate, which gives a steady power output from a fission reactor, every fission gives rise to another fission. This happens because in every fission 2 or 3 neutrons are produced, some are absorbed or lost, but if just one is captured by another fissionable nucleus, the chain reaction will continue. Apex answer = 1
For a chain reaction to occur each vision must produce at least more fission reaction Apex?
In a chain reaction, each fission reaction must produce at least one additional fission reaction to sustain the reaction. This is necessary to achieve a self-sustaining nuclear reaction where each fission event leads to more fission events, releasing energy in the process. Without this multiplication of fission reactions, the chain reaction would not be able to continue and sustain itself.
Describe a characteristic of a fissionable substance that is essential for a chain reaction to sustain itself?
A characteristic of a fissionable substance essential for a chain reaction to sustain itself is the ability to release additional neutrons upon undergoing fission. These neutrons can then continue to collide with other fissionable nuclei, causing a cascade of fission reactions and sustaining the chain reaction.
Why does a nuclear fission reaction generally not result in an uncontrolled chain reaction?
Nuclear fission reactions are controlled in reactors by using materials that absorb excess neutrons, like control rods. This prevents a chain reaction from running out of control. Additionally, reactors are carefully designed and operated to maintain the conditions necessary to sustain controlled fission reactions without escalating into an uncontrolled chain reaction.
What must happen for nuclear reactor to make electricity?
a chain reaction
How is a chain reactor controlled?
A chain reactor is controlled by adjusting the rate of fission reactions to maintain a stable and safe operating condition. This is achieved by controlling the neutron population in the reactor core through mechanisms such as control rods, coolant flow, and moderator density. By carefully managing these factors, operators can regulate the power output of the reactor as needed.
A nucleus captures two neutrons and decays to produce one neutron is this process likely to produce a chain reaction?
Yes, if the nucleus is undergoing fission and releasing additional neutrons upon decay, capturing two neutrons could contribute to a chain reaction by generating more fission events and more neutrons. However, the likelihood of a chain reaction occurring also depends on the specific nucleus involved and the surrounding conditions.
What must metal fuel rods inside a nuclear reactor be bombarded with in order to start a chain reaction?
The metal fuel rods inside a nuclear reactor must be bombarded with neutrons in order to start a chain reaction. This process triggers the fission of uranium atoms in the fuel rods, releasing energy in the form of heat.
Describe a characteristic of a fissionable substance that is essential for a chain-reaction to sustain itself?
A characteristic of a fissionable substance essential for a chain reaction to sustain itself is the ability to efficiently release neutrons upon splitting. This neutron release enables the sustained splitting of more atoms, creating a self-sustaining chain reaction.
What is meant by chain reaction in nuclear reactor?
A chain reaction in a nuclear reactor refers to the process where the fission of one atomic nucleus releases neutrons that go on to induce further fission reactions in other nuclei, leading to a self-sustaining reaction. This continuous releasing of energy is harnessed in nuclear reactors to generate electricity. Proper control measures are in place to manage and regulate the chain reaction to ensure safety and efficiency.
What must happen in order for a nuclear chain reaction to happen?
The number of neutrons existing in the critical core of the reactor must be steady or increasing, if it is decreasing the reaction will reduce and eventually stop. When a nucleus fissions (ie one of U-235) roughly 2.5 neutrons are produced, on average. Some of these are absorbed by the moderator and other incore materials, and some are lost at the core boundaries, but if for every nucleus that is fissioned, one neutron is then absorbed into another U-235 nucleus causing another fission, then the process will continue at a steady rate and we can call that a chain reaction. If there is a surplus of neutrons the population will increase and this could go on exponentially increasing, but this is contolled by the neutron absorbing control rods so that the neutron flux, or reactor power, is maintained at a steady level, for normal steady operation. In order for a nuclear chain reaction to take place, each nucleus must produce an average of one neutron that causes fission of another nucleus.
What reaction must uranium undergo in order to release energy?
Nuclear fission with thermal neutrons
For a fission reaction to fail to be maintained as a chain reaction each fission must produce less than additional fission reaction(s).?
In a continuous chain reaction at a steady rate, which gives a steady power output from a fission reactor, every fission gives rise to another fission. This happens because in every fission 2 or 3 neutrons are produced, some are absorbed or lost, but if just one is captured by another fissionable nucleus, the chain reaction will continue. Apex answer = 1
For a chain reaction to occur each vision must produce at least more fission reaction Apex?
In a chain reaction, each fission reaction must produce at least one additional fission reaction to sustain the reaction. This is necessary to achieve a self-sustaining nuclear reaction where each fission event leads to more fission events, releasing energy in the process. Without this multiplication of fission reactions, the chain reaction would not be able to continue and sustain itself.
