🔍 Key Concepts

• Solid bearing vs. antifriction (rolling element) bearing – how each supports the shaft • Where the relative motion occurs: between shaft and bearing surface, or between rolling elements and races • Common examples of plain journal bearings used on engines and turbines

💭 Think About

• For each choice, ask: does this part normally run directly on a smooth surface with a thin film of oil, or does it use balls/rollers/springs? • Think about which components are typically journal-type or sleeve-type bearings in marine machinery. • Which of these is most clearly designed as a continuous surface supporting a rotating shaft rather than using separate moving elements?

✅ Before You Answer

• Verify which choices are plain (sleeve/journal) bearings rather than rolling-element or flexible-type supports. • Check your understanding: a solid bearing usually has no balls or rollers – just shaft against a bearing surface with lubrication. • Eliminate any option that is primarily a support device or special-purpose mounting, not a simple plain bearing surface.