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Power–head relationship in reaction turbines For a reaction turbine working under a given set of geometric and efficiency conditions, how does the power produced relate to the head of water? Choose the correct completion.

Difficulty: Easy

Is inversely proportional to head
Is directly proportional to head
Is independent of head
Varies with the square of head

Correct Answer: Is directly proportional to head

Explanation:

ConceptShaft power ≈ η_overall · ρ g Q H.

ReasoningFor similar operating conditions (η and Q appropriately related), power scales with head H. At fixed discharge, power is directly proportional to H.

Final AnswerIs directly proportional to head.

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