Question

Choose the correct statement(s) from the following with respect to a ship-generated Kelvin wave pattern in deep water.

• A. A system of transverse waves and divergent waves are observed behind the ship.
• B. A system of transverse waves and divergent waves are observed in front of the ship.
• C. The waves are contained in a sector originating at the bow with a half angle of \( 9^\circ 28' \).
• D. The amplitude of wave components decreases as they propagate.

Hint:

Kelvin wave patterns are a result of a ship's motion through water. These patterns consist of both transverse and divergent waves, and the waves spread in a sector behind the ship with decreasing amplitude.

Answer 1

The Correct Option is A, D

A ship moving through water creates a characteristic wave pattern known as the Kelvin wave pattern. This pattern is composed of two components: transverse waves and divergent waves, both of which are observed behind the ship.

Detailed explanation of the statements:
(A) Correct: Behind the ship, both transverse waves and divergent waves are formed. These are the fundamental components of the Kelvin wave pattern, which propagates in a fan-like pattern from the ship’s wake.
(B) Incorrect: The wave pattern is not formed in front of the ship. Instead, the waves are generated behind the ship due to its motion through the water.
(C) Incorrect: The Kelvin wave pattern is not confined to the sector originating at the bow. The sector angle is typically approximately \( 19^\circ \), not \( 9^\circ 28' \).
(D) Correct: As the Kelvin waves propagate outward from the ship, their amplitude decreases over distance. This is due to the spreading of energy as the waves travel through the water.

Conclusion: The correct statements are (A) and (D).