According to linear water wave theory, at a point on the free surface of a regular wave, the phase difference between the free surface elevation and the horizontal water particle acceleration is ________.
Show Hint
- 0°
- 45°
- 90°
- 135°
The Correct Option is C
Solution and Explanation
In regular waves, the free surface elevation is a sinusoidal function. The water particle motion in regular waves follows circular trajectories in the vertical plane.
Step 2: Phase Difference.
The phase difference between the free surface elevation and the horizontal particle acceleration is found to be 90° based on linear wave theory. This occurs because the maximum acceleration of the water particles happens when the displacement of the free surface is zero.
Step 3: Conclusion.
Thus, the phase difference between the free surface elevation and the horizontal water particle acceleration is 90°.
Correct Answer: (C) 90°.
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