Turbine meters have ______, but water must be moving at sufficient speed before the ______ will start to rotate.

• A. Low Friction Loss, Rotor
• B. High Friction Loss, Rotor
• C. Low Friction Loss, Bearing
• D. Low Resistance, Rotor

Answer: (A)

Turbine meters rely on a rotor that is driven by the flowing water, and they are designed with very low friction inside so the moving water energy is efficiently transferred to rotation. Because of that low friction, once water is moving, the rotor will begin to turn, but you need a sufficient flow speed to overcome static friction and rotor inertia. The part that actually rotates is the rotor, while the bearing just supports it. So the best fit describes having low friction loss and the rotor as the rotating element.