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Critical pressure condition: behavior of discharge (mass flow rate) Complete the statement about nozzles/orifices: The discharge is ________ at the critical pressure ratio. Choose the correct option.

Difficulty: Easy

Zero
Minimum
Maximum
Constant (independent of pressure ratio)

Correct Answer: Maximum

Explanation:

Concept
For compressible flow through a converging nozzle, at the critical pressure ratio the flow becomes choked (Mach 1 at the throat) and the mass flow rate reaches its maximum for the given upstream conditions.

Implication
Further reduction of downstream pressure will not increase the discharge; it remains at the maximum choked value.

Final Answer
Maximum

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