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Nozzle efficiency — definition by heat drops Definition prompt: The ratio of the useful heat drop (actual enthalpy drop converted to kinetic energy) to the isentropic heat drop across a nozzle equals which efficiency? Choose the correct option.

Difficulty: Easy

Condenser efficiency
Nozzle efficiency
Boiler efficiency
Vacuum efficiency

Correct Answer: Nozzle efficiency

Explanation:

Concept/Approach

Nozzle efficiency is defined as η_n = (actual KE at exit)/(ideal KE) = (actual enthalpy drop)/(isentropic enthalpy drop).
It measures how effectively the available heat drop is converted to kinetic energy.

Final Answer
Nozzle efficiency

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