Two streams of electrons are moving parallel to each other in the same direction. They

Options

A. a net repulsion between them
B. a net attraction between them
C. the electric repulsion and magnetic attraction nullify each other
D. the electric repulsion and magnetic repulsion nullify each other

Answer

To solve the question regarding the interaction between two streams of electrons moving parallel to each other in the same direction, we can follow these steps:

### Step 1: Understand the Nature of Electrons
Electrons are negatively charged particles. When two negatively charged particles are brought close to each other, they experience a repulsive force due to their like charges.

### Step 2: Analyze the Motion of Electrons
The question states that the two streams of electrons are moving parallel to each other in the same direction. This means that both streams are aligned and moving in the same path.

### Step 3: Determine the Forces Acting on the Electrons
1. **Electric Force**: Since both streams consist of electrons, they will repel each other due to the electric force. The electric force between two charges is given by Coulomb's law, which states that like charges repel each other.

2. **Magnetic Force**: When charges move, they create a magnetic field around them. According to the right-hand rule, the direction of the magnetic field created by a current (or moving charge) is perpendicular to the direction of the current. However, since both streams are moving in the same direction, the magnetic fields they create will also interact.

### Step 4: Analyze the Interaction of Forces
- The electric repulsion between the two streams of electrons will dominate because they are both negatively charged and are moving parallel to each other.
- The magnetic fields generated by each stream will create an attraction between them, but this effect is typically weaker than the electric repulsion when considering the same magnitude of current.

### Step 5: Conclusion
Given that the electric repulsion is stronger than the magnetic attraction in this scenario, the net force between the two streams of electrons will be repulsive.

Thus, the answer to the question is that there is a **net repulsive force** between the two streams of electrons.

### Final Answer
The net force between the two streams of electrons is **repulsive**.

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