During a nuclear fission event, each incident neutron triggering a split releases_______________?
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Answer: D. more than one new neutrons
Explanation
During each nuclear fission event, the splitting of a heavy nucleus releases more than one new neutron. These newly liberated prompt neutrons are essential for sustaining a continuous self-propagating nuclear fission chain reaction. On average, the fission of a U-235 nucleus releases approximately two to three high-energy free neutrons per event. Nuclear fission occurs when an unstable heavy nucleus absorbs a neutron and splits into smaller fission fragments and free neutrons. Chain reactions require a multiplication factor greater than or equal to one to maintain stable nuclear power generation. Control rods are inserted into reactor cores to absorb excess neutrons and regulate the rate of the fission chain reaction.
Option A is incorrect because releasing zero neutrons would instantly terminate any ongoing nuclear fission chain reaction. Option B is insufficiently precise because releasing only a single neutron would barely sustain a static, non-multiplying reaction. Option C is wrong because fission events statistically yield an average of more than one free neutron to maintain criticality.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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