Why is sound wave called a longitudinal wave ?

Explanation

### Step-by-Step Solution:

1. **Understanding Waves**: A wave is a disturbance that travels through a medium, carrying energy from one place to another. There are different types of waves based on how they propagate and how the particles of the medium move.

2. **Types of Waves**: Waves can be classified into two main types:
- **Longitudinal Waves**: In these waves, the particles of the medium move parallel to the direction of wave propagation.
- **Transverse Waves**: In these waves, the particles of the medium move perpendicular to the direction of wave propagation.

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