🔍 Key Concepts

• Kort nozzle design and purpose around a propeller • Difference between open propellers and ducted or shrouded propellers • How propeller types are named based on blade arrangement vs. surrounding structure

💭 Think About

• Ask yourself: Does a Kort nozzle describe the actual propeller blades, or does it describe something built around the propeller? • Which option best matches a propeller that operates inside a fixed ring or housing that improves thrust, especially at low speeds? • Which choices describe special blade motions (like rotating or vertical blades) instead of a simple propeller with a surrounding nozzle?

✅ Before You Answer

• Identify which choice refers to a propeller with a fixed ring/duct around it • Eliminate options that mainly describe blade motion or arrangement rather than a surrounding structure • Confirm that the selected term is commonly used for tugs and vessels needing high thrust at low speed