🔍 Key Concepts

• Difference between structural spaces (like double bottoms) and tanks used for liquids (like bilge or ballast tanks) • How the inner bottom and outer shell plating create a named space in ship construction • What is meant by the term floor in ship structure and whether it refers to a plate, a frame, or a volume of space

💭 Think About

• Look closely at label J: is the arrow pointing to a structural member (steel plate or frame) or to an enclosed volume between two plates? • Ask yourself: is this region normally used as a designated tank, a general void, or simply the name for the whole structural arrangement at the bottom of the ship? • Consider how the presence of an inner bottom over the shell plating is usually described in basic ship-construction terminology.

✅ Before You Answer

• Verify what the double bottom actually refers to: is it the plates themselves or the space they enclose? • Check whether a bilge tank is always present, or if it is just one possible use of the double-bottom space. • Confirm whether the term floor in naval architecture means an open space you can walk in, or a transverse structural member connecting the shell plating and inner bottom.