What is the primary function of a propeller in a boat?

The primary function of a propeller in a boat is to rotate and power the boat forward or backward. This is achieved through the conversion of rotational motion into thrust, allowing the vessel to move through the water. When the propeller spins, it pushes water behind it, creating a forward or backward force that propels the boat in the desired direction.

In contrast to steering, which involves manipulating the rudder or the boat's helm, the propeller is strictly responsible for propulsion. Buoyancy is a separate principle that relates to the boat's ability to float on water, determined by its design and the volume of water displaced. Stabilizing the boat involves using ballast or hull design features rather than the propeller itself. Thus, the primary role of the propeller is essential for movement, highlighting its importance in boating operations.