Q117 / 270 · NDA 2025 (Phase 2) · General Ability
Consider the following statements with reference to sea waves:
1. The height of waves is determined by wind speed, wind duration, and fetch
2. The energy of a wave is proportional to the square of its height
3. Waves retain most of their energy as they travel across the deep ocean
Which of the statements given above is/are correct?
1. The height of waves is determined by wind speed, wind duration, and fetch
2. The energy of a wave is proportional to the square of its height
3. Waves retain most of their energy as they travel across the deep ocean
Which of the statements given above is/are correct?
- A1 only
- B1 and 2 only
- C2 and 3 only
- Correct answerD1, 2 and 3
Solution
The height of sea waves is primarily determined by three factors: wind speed, the duration for which the wind blows, and the fetch (the distance of open water over which the wind blows). Thus, statement 1 is correct.
The energy of a wave is directly proportional to the square of its height ($E \propto H^2$). Thus, statement 2 is correct.
As waves travel across the deep ocean, they experience very little friction because the water depth is much greater than the wave base. Consequently, they retain most of their energy and can travel thousands of kilometers as swell. Thus, statement 3 is correct.
All three statements are correct.
Answer: 1, 2 and 3
The energy of a wave is directly proportional to the square of its height ($E \propto H^2$). Thus, statement 2 is correct.
As waves travel across the deep ocean, they experience very little friction because the water depth is much greater than the wave base. Consequently, they retain most of their energy and can travel thousands of kilometers as swell. Thus, statement 3 is correct.
All three statements are correct.
Answer: 1, 2 and 3
Hence, the correct answer is option: 'D'.