What will be the path of a charged particle moving along the direction of a uniform magnetic field?

Options

A. Circular path
B. Parabolic path
C. Straight line pathe
D. None of them

Answer

To determine the path of a charged particle moving along the direction of a uniform magnetic field, we can analyze the situation step by step.

### Step-by-Step Solution:

1. **Understanding the Magnetic Force**: The magnetic force acting on a charged particle is given by the equation:
\[ F = Q \cdot v \cdot B \cdot \sin(\theta) \]
where \( F \) is the magnetic force, \( Q \) is the charge of the particle, \( v \) is the velocity of the particle, \( B \) is the magnetic field strength, and \( \theta \) is the angle between the velocity vector and the magnetic field vector.

2. **Identifying the Direction of Motion**: In this case, the charged particle is moving along the direction of the uniform magnetic field. This means that the angle \( \theta \) is either \( 0^\circ \) (if the particle moves in the same direction as the magnetic field) or \( 180^\circ \) (if it moves in the opposite direction).

3. **Calculating the Force**:
- If \( \theta = 0^\circ \):
\[ F = Q \cdot v \cdot B \cdot \sin(0^\circ) = 0 \]
- If \( \theta = 180^\circ \):
\[ F = Q \cdot v \cdot B \cdot \sin(180^\circ) = 0 \]
In both cases, the magnetic force \( F \) is zero.

4. **Analyzing the Motion**: Since the magnetic force acting on the charged particle is zero, there are no forces acting to change its direction of motion. Therefore, the particle will continue to move in a straight line.

5. **Conclusion**: The path of the charged particle moving along the direction of a uniform magnetic field will be a straight line. It will not deviate from its path, regardless of whether it is moving with or against the magnetic field.

### Final Answer:
The path of the charged particle will be a **straight line**.

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