Two parallel beams of positrons moving in the same direction will

Options

A. Repel each other
B. Will not interact with each other
C. Attract each other
D. Be deflected normal to the plane containing the two beams

Answer

To solve the question of whether two parallel beams of positrons moving in the same direction will repel, attract, or interact in some other way, we can follow these steps:

### Step 1: Understand the nature of positrons
Positrons are the antiparticles of electrons and carry a positive charge. Since they are positively charged particles, they can be treated similarly to a current flowing in a wire.

**Hint:** Recall that the flow of positive charge is equivalent to the flow of current.

### Step 2: Represent the beams as currents
We can represent each beam of positrons as a current. If we have two beams of positrons moving in the same direction, we can denote them as two parallel currents flowing upward.

**Hint:** Think of the definition of current as the flow of charge and how it relates to magnetic fields.

### Step 3: Determine the magnetic field produced by each beam
According to the right-hand thumb rule, if you point your thumb in the direction of the current (the direction of the positrons), your curled fingers will show the direction of the magnetic field produced by that current.

- For the first beam (Beam 1), the magnetic field will be directed inward (into the page).
- For the second beam (Beam 2), the magnetic field will also be directed inward (into the page).

**Hint:** Use the right-hand rule to visualize the magnetic field direction produced by each beam.

### Step 4: Analyze the interaction of the beams
When the two beams are placed in each other's magnetic fields, we need to consider the forces acting on them due to these magnetic fields.

- The magnetic field produced by Beam 1 will exert a force on Beam 2.
- The magnetic field produced by Beam 2 will exert a force on Beam 1.

Using the right-hand palm rule (or Fleming’s left-hand rule), we can determine the direction of the force on each beam.

**Hint:** Remember that like currents attract and opposite currents repel.

### Step 5: Determine the nature of the interaction
Since both beams are moving in the same direction and are positively charged (like currents), they will attract each other. This is consistent with the principle that parallel currents attract.

**Hint:** Think about how two wires carrying current in the same direction behave.

### Conclusion
Thus, the two parallel beams of positrons moving in the same direction will **attract each other**.

**Final Answer:** The two parallel beams of positrons moving in the same direction will attract each other.

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