🔍 Key Concepts

• Righting moment as the ship’s tendency to return to upright when heeled • Relationship between displacement (Δ), righting arm (GZ), and righting moment in basic stability formula • What the different centers (G, KG, LCG) represent in ship stability

💭 Think About

• When a vessel is heeled, which quantity actually creates a lever arm between weight and buoyancy? • Which of the listed options is measured as a distance that, when multiplied by the ship’s weight (displacement), gives a moment? • Look at each choice and ask: is this a point, a vertical distance, a longitudinal distance, or a transverse lever arm used in stability curves?

✅ Before You Answer

• Remember that moment = force × distance; here, the force is the vessel’s displacement (weight) • Identify which option corresponds to the transverse lever arm used on a righting arm curve vs. which are just positions of the center of gravity • Verify which symbol is used in stability textbooks and exam questions for the righting arm that varies with heel angle