A proton exerts a force on a proton which is

Options

A. Gravitational
B. Electromagnetic
C. nuclear
D. Weak

Answer

To solve the question "A proton exerts a force on a proton which is," we need to analyze the types of forces that can act between two protons.

### Step-by-Step Solution:

1. **Identify the Nature of Protons**:
- Protons are positively charged particles and they also have mass.

2. **Consider the Forces Acting Between Protons**:
- **Gravitational Force**: Since protons have mass, they will exert a gravitational force on each other. However, this force is extremely weak compared to other forces at the atomic level.
- **Electromagnetic Force**: Because protons are charged, they will exert an electromagnetic force on each other. This force is significant and is the primary force acting between charged particles.
- **Nuclear Force**: At very short distances (on the order of the size of an atomic nucleus), protons can also exert a strong nuclear force on each other. This force is responsible for holding the nucleus together.
- **Weak Force**: The weak force is responsible for certain types of particle interactions (like beta decay) but does not play a role in the interaction between two protons.

3. **Evaluate the Options**:
- Gravitational Force: Yes, protons exert gravitational force on each other.
- Electromagnetic Force: Yes, protons exert electromagnetic force on each other due to their charge.
- Nuclear Force: Yes, at very short distances, protons can exert a nuclear force on each other.
- Weak Force: No, weak force does not apply in this context as it is not a force that acts between two protons in the way described.

4. **Conclusion**:
- The forces that a proton exerts on another proton are gravitational, electromagnetic, and nuclear forces. The weak force does not apply here.

### Final Answer:
A proton exerts a gravitational force, an electromagnetic force, and a nuclear force on another proton.

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