Light wave is travelling along X-axis in a medium. Which of the following can represent wavefront for this light wave ?

Options

A. `x = 0`
B. `x = c`
C. `x^2 + y^2 + z^2 = c^2`
D. `z = c`

Explanation

To solve the question regarding the representation of wavefronts for a light wave traveling along the X-axis in a medium, we can follow these steps:

### Step 1: Understanding Wavefronts
A wavefront is defined as the surface over which an oscillation (such as a light wave) has a constant phase. For a light wave traveling in a particular direction, the wavefronts are perpendicular to the direction of propagation.

### Step 2: Direction of Propagation
Since the light wave is traveling along the X-axis, we need to identify the plane that is perpendicular to this direction. The direction of propagation is along the X-axis, which means the wavefronts will be in a plane that is perpendicular to the X-axis.

### Step 3: Identifying the Perpendicular Plane
The plane that is perpendicular to the X-axis can be represented by the YZ-plane. This is because any point in the YZ-plane has an X-coordinate of 0, meaning it does not change as we move in the Y and Z directions.

### Step 4: Equations of the YZ-plane
The equations that represent the YZ-plane are:
- \( x = 0 \) (this represents the plane where the X-coordinate is zero)
- \( x = c \) (this represents another plane parallel to the YZ-plane at a distance 'c' along the X-axis)

### Conclusion
Therefore, the wavefronts for the light wave traveling along the X-axis can be represented by the equations:
- \( x = 0 \)
- \( x = c \)

### Final Answer
The correct representations of the wavefront for the light wave traveling along the X-axis are \( x = 0 \) and \( x = c \).

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