For geometrically similar centrifugal pumps operating under similar conditions, if the rotational speed is doubled, the ideal pump head changes by a factor of:
Correct answer: A. Four
- A. Four
- B. Two
- C. Six
- D. Eight
Explanation
The pump affinity law states that head varies with the square of rotational speed. Therefore, doubling speed increases the ideal head by 2², or four times.
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About Hydraulics and Water Resources
Hydraulics studies fluid properties, pressure, buoyancy, continuity, Bernoulli's equation, momentum, pipe flow, open-channel flow and hydraulic machines. Water resources extends these principles to pumps, turbines, reservoirs, irrigation, floods and hydrology, while distinguishing laminar from turbulent flow and uniform from gradually varied channel flow.
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