973. As the propeller turns, voids are formed on the trailing and leading edges of the propeller blades causing a loss of propulsive efficiency, pitting of the blades, and vibration. Which term defines this effect?

Cavitation is the correct answer; it describes the formation and collapse of vapor-filled cavities on propeller blades, resulting in reduced efficiency, pitting, and vibration. This phenomenon occurs when local pressure drops below vapor pressure, leading to bubble collapse and surface damage. Other options—slip, advance, and edging—do not accurately represent this blade-flow effect.