Dynamic forces are defined as?

• A. Forces that affect stability from outside the boat; wind and waves are an example.
• B. Forces that affect stability from inside the boat.
• C. Forces due to hull shape.
• D. Forces from the engine.

Answer: (A)

Dynamic forces are the external disturbances that affect a boat’s stability and motion. They come from outside the boat and interact with the hull as it moves through the water, such as wind acting on the vessel or rain and spray, and wave action that pushes, lifts, and shocks the hull. These forces vary with weather, sea state, and the boat’s speed, and they drive how the boat heels, rolls, and trims. Other options describe forces that originate inside the boat (like crew movement or ballast shifts), or forces tied to hull design or propulsion, which aren’t the external, environmental disturbances meant by dynamic forces.