🔍 Key Concepts

• Relative density (specific gravity) of common rope materials • Which synthetic fibers float on water vs. which sink • How material composition affects weight for the same diameter/length of rope

💭 Think About

• Think about which of these rope materials will FLOAT in water and which will SINK. The ones that float usually have a lower density. • Among the synthetic fibers (Dacron and Nylon) and natural fiber (Manila), which group is generally heavier than water? • Compare the general feel/weight of a coil of natural fiber line vs. a bright-colored plastic-type line of the same size.

✅ Before You Answer

• Identify which material has a specific gravity less than 1.0 (lighter than water). • Confirm which rope types are commonly used as heaving lines or water-rescue lines because they float. • Eliminate any materials you know are heavier than water and would normally sink.