Power and flow in turbines: dependence of work on water weight flow per second Consider a water turbine operating at a given head. How does the work done (per second, i.e., power) relate to the weight of water flowing per second? Choose the most accurate relation.
Mechanical Engineering
Hydraulic Machines
Difficulty: Easy
Choose an option
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AIs directly proportional to the weight flow per second
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BIs inversely proportional to the weight flow per second
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CIs independent of the weight flow per second
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DVaries with the square of the weight flow per second
Answer
Correct Answer: Is directly proportional to the weight flow per second
Explanation
Given / ConceptHydraulic power available = ρ g Q H, where ρ g Q is the weight flow per second and H is head.
ReasoningAt fixed head H, power (and thus work per second) is directly proportional to the weight flow ρ g Q. Doubling the weight flow doubles the available power and the work done per second (neglecting losses).
Final AnswerIs directly proportional to the weight flow per second.