🔍 Key Concepts

• Transverse movement of liquid in a tank and its effect on stability • Meaning of metacentric height (GM) and how it relates to a vessel feeling ‘stiff’ or ‘tender’ • Difference between buoyancy/trim/draft and internal tank effects

💭 Think About

• When a tank is only partly full, what happens to the liquid when the ship heels to one side? How does that affect the ship’s tendency to return upright? • Which option describes a negative stability effect created inside the ship, rather than an external change like draft or trim? • Think about which choice refers to a known stability hazard taught with slack tanks and sounding reports.

✅ Before You Answer

• Identify which term is specifically associated with slack tanks in stability discussions • Eliminate any options that normally would improve stability or are not directly linked to internal liquid motion • Confirm which choice represents an effect that reduces metacentric height (GM) and makes the ship more tender