🔍 Key Concepts

• Demulsibility in lubrication engineering refers to how a lube oil behaves when it becomes contaminated with water • Why it is important for lube oil in engines and gears to either mix with or separate from water • How water contamination is normally removed from lube oil (settling, centrifuging, draining)

💭 Think About

• Ask yourself: in real shipboard practice, what property of lube oil makes it easier to remove water from a sump or purifier? • Think about which option describes a property of the oil itself, rather than a condition or a measurement of the system. • Which choice would be most important for maintaining effective lubrication when sea water or condensation enters the system?

✅ Before You Answer

• Verify which option actually describes a property of the oil (not a system reading or a mixture). • Check which choice directly relates to how oil and water behave together when mixed. • Eliminate any option that talks about temperature or about mixing different oils rather than oil and water.