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 inertia of the sample is too low for efficient fission. C) nuclei repel each other due to their positive charges. D) the heat produced by the spontaneous fission of some nuclei is insufficient.

Question

Quizplus · Accepted Answer

A sample below critical mass does not have enough material to sustain a chain reaction because too many neutrons escape without initiating fission. Critical mass is the minimum size that a sample of fissile material needs to be in order to support a chain reaction.

A Sample of U235 That Is Below the Critical Mass

A Sample of U²³⁵ That Is Below the Critical Mass