Nuclear fission can be explained by

Options

A. Liquid droplet theory
B. Yakawa `pi` - meson theory
C. Independent particle model of the nucleus
D. Proton-proton cycle

Answer

To solve the question "Nuclear fission can be explained by," we need to analyze the given options and identify the correct theory that describes the process of nuclear fission.

### Step-by-Step Solution:

1. **Understanding Nuclear Fission**:
- Nuclear fission is the process where a heavy nucleus splits into two or more lighter nuclei, along with the release of energy and neutrons. This process is fundamental in nuclear reactors and atomic bombs.

2. **Analyzing the Options**:
- **Option 1: Liquid Droplet Theory**: This theory describes the nucleus as a collection of nucleons (protons and neutrons) that behave like a liquid drop. It explains the stability and behavior of the nucleus, including fission.
- **Option 2: Jacobi-Pi-Mason Theory**: This theory is not commonly associated with nuclear fission and does not provide a clear explanation of the fission process.
- **Option 3: Independent Particle Model of the Nucleus**: This model describes nucleons moving independently in a potential well but does not specifically address the fission process.
- **Option 4: Proton-Proton Cycle**: This cycle describes a series of nuclear reactions that occur in stars, primarily involving hydrogen nuclei fusing into helium. It is not related to nuclear fission.

3. **Identifying the Correct Answer**:
- The **Liquid Droplet Theory** is the most appropriate model to explain nuclear fission. It accounts for the behavior of the nucleus as a drop of liquid, which can deform and eventually split into smaller droplets (nuclei), thus explaining the fission process.

4. **Conclusion**:
- Therefore, the correct answer is **Option 1: Liquid Droplet Theory**.

### Final Answer:
Nuclear fission can be explained by the **Liquid Droplet Theory**.

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