What does the term "frictional drag" refer to in scuba diving?

The term "frictional drag" specifically refers to the resistance encountered by a diver's body as it moves through the water. This concept is crucial in understanding hydrodynamics in scuba diving. As a diver swims, they experience drag due to the water's viscosity and their body's surface area, which affects how efficiently they can move. The greater the surface area and the faster the movement, the more drag is encountered.

While the resistance experienced by a diver's gear can contribute to overall drag, it is not solely classified as frictional drag. Current drag involves the influence of water movement on the diver, which is a separate consideration from the drag generated by the diver's own movement through the water. Additionally, underwater obstacles may exert forces on a diver but are not classified as frictional drag; this involves different types of interactions. Understanding frictional drag helps divers optimize their movements to swim more efficiently, conserve energy, and enhance their overall diving experience.