In a transverse wave, the particles of the medium

Options

A. vibrate in a direction perpendicular to the direction of the propagation.
B. vibrate in a direction parallel to the direction or of the propagation
C. move in circle
D. move in ellipse

Explanation

**Step-by-Step Solution:**

1. **Understanding Transverse Waves**: A transverse wave is a type of wave where the motion of the particles of the medium is perpendicular to the direction of the wave's propagation. This means that if the wave is moving in one direction, the particles of the medium are moving up and down or side to side.

2. **Identifying Directions**: In a transverse wave, if we consider the wave traveling along the x-axis (the direction of propagation), the particles of the medium will vibrate along the y-axis (the direction perpendicular to the x-axis).

3. **Analyzing the Options**:
- Option 1: "Vibrate in a direction perpendicular to the direction of propagation" - This is correct as explained above.
- Option 2: "Vibrate in a direction parallel to the direction of propagation" - This is incorrect because in a transverse wave, the vibration is not in the same direction as the wave travels.
- Option 3: "Move in a circle" - This is not applicable to transverse waves.
- Option 4: "Move in ellipse" - This is also not applicable to transverse waves.

4. **Conclusion**: Based on the analysis, the correct answer is that in a transverse wave, the particles of the medium vibrate in a direction perpendicular to the direction of propagation.

**Final Answer**: The correct option is 1: "Vibrate in a direction perpendicular to the direction of propagation."

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