An `alpha-` particle moves from `E` to `W` in a magnetic field perpendicular to the plane of the paper and into the paper. The particle is defelcted towards

Options

A. East
B. West
C. South
D. North

Answer

To solve the problem, we need to determine the direction in which an alpha particle, moving from East to West, will be deflected when it enters a magnetic field that is directed into the paper (perpendicular to the plane of the paper).

### Step-by-Step Solution:

1. **Identify the Direction of Motion of the Alpha Particle**:
- The alpha particle is moving from East to West.

2. **Identify the Direction of the Magnetic Field**:
- The magnetic field is directed into the paper. This is often represented by dots (•) on the paper, indicating that the field lines are coming out towards you.

3. **Determine the Charge of the Alpha Particle**:
- An alpha particle is a positively charged particle (it consists of 2 protons and 2 neutrons).

4. **Use the Right-Hand Rule**:
- To find the direction of the force acting on the charged particle due to the magnetic field, we can use the right-hand rule.
- Point your thumb in the direction of the velocity of the particle (East to West).
- Point your fingers in the direction of the magnetic field (into the paper).
- Your palm will then face the direction of the force acting on a positive charge.

5. **Determine the Direction of Deflection**:
- According to the right-hand rule, the force acting on the positively charged alpha particle will be directed downwards (towards the South).

6. **Conclusion**:
- Therefore, the alpha particle will be deflected towards the South.

### Final Answer:
The alpha particle is deflected towards the South.

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