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Maximum propulsive efficiency for jet-propelled ship with side inlets A ship uses jet propulsion with inlet orifices at right angles to its motion. What is the maximum possible propulsive efficiency for this configuration? Choose the correct percentage.

Difficulty: Medium

Correct Answer: 50%

Explanation:

Concept
Propulsive efficiency η_p = (useful power to ship) / (jet power), maximized when jet and ship speeds are optimally related.

Result for side inlets
For inlets at right angles to motion, analysis of momentum and energy shows a theoretical maximum η_p of 50%.

Common pitfalls
Confusing this with axial inlets or aircraft jets where the optimal values differ.

Final Answer
50%

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