Which of the following statement(s) is/are correct about strip theory?
Show Hint
- It can be used to calculate the surge added mass
- It is a two-dimensional theory
- It can be used to calculate the pitch added mass
- It can be used to calculate the coupled sway, roll, and yaw added mass
The Correct Option is B
Solution and Explanation
Step 1: Understand the concept of strip theory.
Strip theory is a two-dimensional hydrodynamic theory used in naval architecture. It simplifies the three-dimensional body of a ship into two-dimensional cross-sections (strips) to analyze hydrodynamic forces and added masses. It is particularly useful for analyzing motions such as heave, pitch, sway, roll, and yaw in a linearized form.
Step 2: Analyze the given statements.
Statement (A): Incorrect. Strip theory does not calculate the surge added mass directly, as surge involves longitudinal motion, which requires a fully three-dimensional analysis.
Statement (B): Correct. Strip theory is a two-dimensional approach, analyzing individual cross-sections of a ship rather than the entire three-dimensional structure.
Statement (C): Correct. Strip theory can calculate added masses for vertical motions such as pitch and heave, as these involve hydrodynamic interactions captured in two-dimensional cross-sections.
Statement (D):Correct. Strip theory can handle coupled motions like sway, roll, and yaw by approximating the interactions using cross-sectional hydrodynamics.
Conclusion: The correct statements about strip theory are: (B) It is a two-dimensional theory.
(C) It can be used to calculate the pitch added mass.
(D) It can be used to calculate the coupled sway, roll, and yaw added mass.
Top Questions on Naval Engineering
A steel deck plate of a tanker is supported by two longitudinal stiffeners as shown in the figure. The width of the plate is \( a \) and its length is 5 times the width. Assume that the long edge is simply supported, and the short edge is free. The plate is loaded by a distributed pressure, \( p = p_0 \sin\left(\frac{\pi y}{a}\right) \), where \( p_0 \) is the pressure at \( y = a/2 \). The flexural rigidity of the plate is \( D \). The plate equation is given by
- GATE NM - 2024
- Naval Architecture and Ocean Engineering
- Naval Engineering
Consider the matrices
\( M = \begin{pmatrix} 2 & 1 \\ 0 & 2 \end{pmatrix} \)
\( N = \begin{pmatrix} 1 & 0 & 0 \\ 1 & 2 & 0 \\ 1 & 1 & 0 \end{pmatrix} \)
Which one of the following is true?- GATE NM - 2024
- Naval Architecture and Ocean Engineering
- Naval Engineering
A ship with a standard right-handed coordinate system has positive \(x\), \(y\), and \(z\) axes respectively pointing towards bow, starboard, and down as shown in the figure. If the ship takes a starboard turn, then the drift angle, sway velocity, and the heel angle of the ship for a steady yaw rate respectively are:
- GATE NM - 2024
- Naval Architecture and Ocean Engineering
- Naval Engineering
- A ship with controls fixed is modeled as a two degrees of freedom system. For the linear maneuvering equations of motion for coupled sway and yaw, if the derived eigenvalues are real and negative, then the ship must possess:
- GATE NM - 2024
- Naval Architecture and Ocean Engineering
- Naval Engineering
- Which one of the following cooling systems is used in large marine diesel engines?
- GATE NM - 2024
- Naval Architecture and Ocean Engineering
- Naval Engineering
Questions Asked in GATE NM exam
- If \( P e^x = Q e^{-x} \) for all real values of \( x \), which one of the following statements is true?
Bird : Nest :: Bee : __________
Select the correct option to complete the analogy.- Consider the function \( f(x) = |x| - 1 \). Which of the following statements is/are true in the interval \([-10, 10]\)?
- GATE NM - 2025
- Continuity and differentiability
A closed system is undergoing a reversible process 1–P–2 from state 1 to 2, as shown in the figure, where X and Y are thermodynamic properties. An irreversible process 2–Q–1 brings the system back from 2 to 1. The net change in entropy of the system and surroundings during the above-mentioned cycle are _______ respectively.
- GATE NM - 2025
- Thermodynamics
A ship of 3300 tonne displacement is undergoing an inclining experiment in seawater of density 1025 kg/m\(^3\). A mass of 6 tonne is displaced transversely by 12 m as shown in the figure. This results in a 0.12 m deflection of a 11 m long pendulum suspended from the centerline. The transverse metacenter of the ship is located at 7.25 m above the keel.
The distance of the center of gravity from the keel is ________ m (rounded off to two decimal places).
- GATE NM - 2025
- Ship Dynamics