🔍 Key Concepts

• Six degrees of freedom of a vessel’s movement (surge, sway, heave, roll, pitch, yaw) • Difference between longitudinal vs transverse vs vertical motions • What trim describes on a ship (related to loading/fore-and-aft attitude), not how it moves in a seaway

💭 Think About

• First list the true motions of a vessel in three dimensions and separate rotational motions from straight-line motions. • Ask yourself which options describe how the hull actually moves in response to waves, and which one instead describes a condition or attitude of the ship. • Think: which of these terms would change if you shift weight forward or aft while the ship is at rest, versus which change because the ship is actively moving in a seaway?

✅ Before You Answer

• Be sure you can name the three rotational motions about the ship’s axes (longitudinal, transverse, vertical). • Confirm which option describes a fore-and-aft difference in draft rather than a dynamic motion. • Before choosing, verify that each remaining option can happen even if the ship’s loading condition does NOT change, only the sea state or maneuvering.