A sample of U235 that is below the critical mass will not sustain a chain reaction because

A. too many neutrons escape through the surface of the sample without initiating fission.
B. the heat produced by the spontaneous fission of some nuclei is insufficient.
C. the inertia of the sample is too low for efficient fission.
D. nuclei repel each other due to their positive charges.


Answer: A

Physics & Space Science

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