🔍 Key Concepts

• How a contact tachometer with a rubber tip actually measures RPM • Where the adapter with small convex rubber tip must touch the rotating shaft • Difference between measuring at the end of a shaft versus along its side

💭 Think About

• Look closely at the illustration: where is the rubber-tipped adapter positioned relative to the shaft it measures? • Would a small convex tip make better, safer contact on the flat end of a shaft, or along the curved side of a moving shaft? • Which options mention a physical location on the shaft itself, and which refer to other machinery parts that might not be shafts at all?

✅ Before You Answer

• Verify how a handheld/contact tachometer is normally applied to a rotating shaft in practice. • Check which answer choices describe an actual location on the shaft rather than other components (like impellers or transmitters). • Make sure the choice you pick matches what the small convex rubber tip in the drawing could realistically press against while the shaft turns.