🔍 Key Concepts

• Stiff vessel vs tender vessel (what GM and roll period mean for each) • Effect of moving weights up or down on the vessel’s center of gravity (G) and metacentric height (GM) • How weight distribution fore-and-aft or athwartships can change rolling behavior

💭 Think About

• Think about what makes a vessel’s roll very quick and uncomfortable. Do you want to make GM bigger or smaller for a stiff vessel? • Which choice will tend to raise the center of gravity (G) and thus reduce GM, leading to a longer, softer roll? • For each option, imagine whether you are putting weight high or low, and close to or away from the centerline, and how that affects stability and roll period.

✅ Before You Answer

• Identify which options raise the center of gravity versus which lower it • Check which option would lengthen the roll period (slower, more comfortable roll) instead of making it quicker • Verify which options change initial stability (GM) significantly, and in which direction