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Nuclear fission basics: average neutrons from U-235 fission On average, how many fast neutrons are produced per fission of U-235 in a thermal reactor context? Choose the correct option.

Difficulty: Easy

2.46
24.6
246
2460

Correct Answer: 2.46

Explanation:

Given data

Nuclide: U-235 undergoing fission by thermal neutron absorption.

Concept
A single U-235 fission typically releases ~2–3 fast neutrons. Standard reference value ≈ 2.43–2.47; a commonly used nominal figure is 2.46.

Check
Order of magnitude must be ~2–3, not tens or hundreds.

Final Answer
2.46

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