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Choked flow in a convergent–divergent steam nozzle Statement: In a C–D nozzle, the mass discharge rate depends on the initial (inlet) steam conditions and the throat area (once choked), not on the exit pressure. Decide whether the statement is correct.

Difficulty: Easy

True
False

Correct Answer: True

Explanation:

ConceptAfter the back pressure is reduced to the critical (choked) value, the throat Mach number is 1. The mass flow then becomes a function of inlet state and throat area only; further reduction of exit pressure does not increase discharge.

Final AnswerTrue

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