A ballast tank is one-third full when...

A ballast tank is one-third full when...

Question 1 of 270705eccef9fbacbc34ba4d46993

A ballast tank is one-third full when additional ballast is added until it is two-thirds full. The increased amount of liquid in the tank will have the greatest influence on the __________.

Question 1 of 27070

Q

A ballast tank is one-third full when additional ballast is added until it is two-thirds full. The increased amount of liquid in the tank will have the greatest influence on the __________.

🔍 Key Concepts

• Free surface effect and how it changes as a tank becomes more or less full • Difference between effects on stability versus effects on center of gravity (G) • When a tank is partially filled, how the moment of inertia of the liquid surface changes with depth

💭 Think About

• Think about when free surface effect is at its maximum: is it when a tank is nearly empty, nearly full, or about half full? • As you add more liquid from 1/3 to 2/3 full, what happens to the breadth of the free surface and the weight of the liquid? • Which of the listed options is most directly affected by changing the amount of liquid in a single transverse ballast tank while the ship’s overall dimensions stay the same?

✅ Before You Answer

• Recall that free surface effect depends on the area (second moment of area) of the liquid surface, not simply on the volume of liquid. • Ask yourself whether MT1 (moment to trim 1 inch) changes mainly with longitudinal weight distribution or with changing the depth in one tank. • Consider whether a virtual rise in G is a cause or an effect of free surface, and which option is more fundamental in this situation.