🔍 Key Concepts
• Center of Buoyancy (B) moves with the shape and position of the underwater volume of the hull or MODU
• Metacenter (M) and its relation to stability: positive, neutral, and negative stability conditions
• The line of action of the buoyant force always passes through the center of buoyancy and is compared with the vessel’s center of gravity (G) to assess stability
💭 Think About
• Think about what physically happens to the underwater shape and the center of buoyancy when the MODU heels or is displaced slightly.
• Under which stability condition(s) are B, M, and G aligned vertically, and how does that relate to the definition of positive, neutral, or negative stability?
• Is the metacenter a fixed point for all angles of heel, or is it defined specifically for small angles and related to the geometry of the displaced volume?
✅ Before You Answer
• Be clear on the definitions of positive, neutral, and negative stability in terms of the positions of G, B, and M.
• Remember that the buoyant force always acts vertically upward through the instantaneous center of buoyancy (B), not necessarily through M or G.
• Verify under which condition G, B, and M lie on the same vertical line after a small disturbance.