Fission Reaction: How Many Neutrons Needed for Chain Reaction?

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Discussion Overview

The discussion revolves around the conditions necessary for sustaining a chain reaction in a fission process, specifically focusing on the number of neutrons released and their role in initiating subsequent fission events. The scope includes theoretical aspects of nuclear fission and the requirements for a continuous chain reaction.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Homework-related

Main Points Raised

  • One participant states that to sustain a chain reaction, at least one of the three neutrons released must initiate another fission reaction.
  • Another participant notes that the neutrons released are typically fast neutrons and that their energy must be reduced to thermal levels for fission to occur in materials with high cross-sections for thermal neutrons.
  • A participant questions whether the original post is a homework question and suggests moving the discussion to a homework section with a proper template.

Areas of Agreement / Disagreement

Participants generally agree that at least one neutron must cause another fission reaction for a chain reaction to be sustained. However, there are differing views on the specifics of neutron energy and the context of the question.

Contextual Notes

There are assumptions regarding the types of fissionable materials and their cross-sections, as well as the energy states of the neutrons involved, which remain unresolved in the discussion.

gurumi
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a certain fission reaction releases 3 neutrons.

how many of these neutrons must go on to produce a subsequent fission if a chain reaction is to be sustained?
 
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What do you think and why?
 
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is this homework ? looks like it

how about posting in the homework section and use the proper template
and show us what you have discovered so far in your research on the subject :smile:Dave
 
To sustain a chain reaction each individual reaction must produce at least one more reaction so at least one of the three neutrons released in a reaction must result in another fission reaction for the reaction to be sustained. The released neutrons will normally be highly energetic fast neutrons and at least for fissionable materials with high cross-sections for thermal neutrons, the energy of the neutrons must be reduced to thermal energies before a fission reaction is likely to take place.
 

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