A light wave can travel

Options

A. in vacuum
B. in vacuum only
C. in a meterial medium
D. in a meterial medium only.

Answer

To solve the question regarding the travel of light waves, we will analyze each option provided and determine the correct answers based on the properties of light.

### Step-by-Step Solution:

1. **Understanding Light Waves**:
- Light waves are electromagnetic waves that can travel through different mediums. They are classified as transverse waves.

2. **Analyzing Option 1 (In vacuum)**:
- Light can travel in a vacuum because it does not require a medium to propagate. In fact, the speed of light is fastest in a vacuum (approximately \(3 \times 10^8\) m/s).
- **Conclusion**: This option is correct.

3. **Analyzing Option 2 (In vacuum only)**:
- This option suggests that light can only travel in a vacuum and not in any other medium. However, this is incorrect because light can also travel through various materials (like air, water, glass, etc.).
- **Conclusion**: This option is incorrect.

4. **Analyzing Option 3 (In a material medium)**:
- Light can also travel through material mediums such as air, water, glass, etc. The speed of light is slower in these mediums compared to a vacuum, but it can still propagate through them.
- **Conclusion**: This option is correct.

5. **Analyzing Option 4 (In a material medium only)**:
- This option implies that light can only travel in material mediums and not in a vacuum. This is incorrect, as we established that light can travel in a vacuum as well.
- **Conclusion**: This option is incorrect.

### Final Answer:
The correct options are **Option 1 (In vacuum)** and **Option 3 (In a material medium)**.

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