If two light nuclei are fused together in nuclear reaction, the average energy per nucleon

Options

A. Increases
B. Decreases
C. Cannot be determined
D. Remains same

Explanation

To solve the question regarding the average energy per nucleon when two light nuclei are fused together in a nuclear reaction, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Nuclear Fusion**:
- Nuclear fusion is a process where two light atomic nuclei combine to form a heavier nucleus. This process releases energy due to the mass defect.

2. **Mass Defect**:
- The mass defect is defined as the difference between the mass of the reactants (the original nuclei) and the mass of the products (the fused nucleus).
- In fusion, the mass of the resulting nucleus is less than the total mass of the original nuclei.

3. **Energy Release**:
- According to Einstein's equation \(E=mc^2\), the mass defect is converted into energy. This energy is released during the fusion process.
- The energy released is distributed among the nucleons (protons and neutrons) in the new nucleus.

4. **Average Energy per Nucleon**:
- The average energy per nucleon is calculated by dividing the total energy released by the number of nucleons in the product nucleus.
- Since energy is released during fusion, the average energy per nucleon in the resulting nucleus will be lower than that in the original nuclei.

5. **Conclusion**:
- Therefore, when two light nuclei fuse together, the average energy per nucleon decreases.

### Final Answer:
The average energy per nucleon **decreases** when two light nuclei are fused together in a nuclear reaction.

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