Which specific category of neutrons exhibits the highest effectiveness in triggering nuclear fission_________________?
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Answer: B. slow
Explanation
Slow neutrons possess lower kinetic energy, allowing them to interact easily with fissile heavy nuclei. This low speed increases the interaction cross-section for neutron capture and subsequent fission events. Thermalized slow neutrons are therefore far more effective at triggering sustained nuclear chain reactions. Fast neutrons released during fission travel at high speeds and are less likely to cause splitting. Reactor moderators slow down fast neutrons through repeated elastic collisions with light nuclei. Uranium-235 has a very high fission cross-section when bombarded with slow thermalized neutrons.
Thermal nuclear reactors rely entirely on moderators to slow down neutrons and sustain power production. Controlling slow neutron populations allows operators to regulate nuclear reactor power output safely. Understanding neutron energy spectra is fundamental to nuclear reactor physics and core design. Fast neutrons have high kinetic energy and require moderation before they efficiently trigger uranium fission. In bulk describes material quantity rather than a specific subatomic neutron energy classification. Static and activated terms do not represent standard neutron kinetic energy categories in reactor physics.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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