A beam of electrons and protons move parallel to each other in the same direction, then they

Options

A. Attract each other
B. Repel each other
C. No relation
D. Neither attract nor repel

Answer

To solve the question regarding the interaction between a beam of electrons and protons moving parallel to each other, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Charges**:
- Electrons have a negative charge (-e) and protons have a positive charge (+e).

2. **Determine the Direction of Current**:
- The flow of electrons constitutes a current, but since electrons are negatively charged, the conventional current (I) is considered to flow in the opposite direction to the movement of electrons.
- If the electrons are moving in a certain direction, the current (I1) due to the electron beam will flow in the opposite direction.
- For protons, which are positively charged, the current (I2) flows in the same direction as the movement of protons.

3. **Establish the Relationship Between the Currents**:
- Since the electrons and protons are moving parallel to each other but in opposite directions of their respective currents, we can denote:
- Current due to electrons (I1) flows in one direction.
- Current due to protons (I2) flows in the same direction as the protons.

4. **Determine the Interaction Between Currents**:
- According to the right-hand rule and the principles of electromagnetism, when two currents flow in opposite directions (I1 and I2 are antiparallel), they will repel each other.
- Therefore, the interaction between the two beams will result in a repulsive force.

5. **Conclusion**:
- Since the currents are antiparallel, the beam of electrons and protons will repel each other.

### Final Answer:
The beam of electrons and protons moving parallel to each other will repel each other.

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