What is meant by "hydrostatic pressure"?

Hydrostatic pressure refers to the pressure exerted by a fluid at rest due to the weight of the fluid above it, influenced by gravitational pull. As you descend underwater, the weight of the water column above you increases, resulting in higher pressure exerted on your body and any objects in the water. This pressure increases by approximately one atmosphere (atm) for every 10 meters (33 feet) of seawater depth.

Understanding hydrostatic pressure is crucial for scuba divers, as it affects buoyancy, gas compression, and the body's physiological responses during dives. For instance, hydrostatic pressure influences how gases behave in the body, which is essential for avoiding issues like decompression sickness and ensuring safe ascent rates.

The other options touch on related concepts but do not accurately define hydrostatic pressure. The pressure exerted by a moving fluid relates more to dynamic pressure, buoyancy involves the differences in pressure to allow objects to float or sink, and pressure felt in the lungs during ascent refers more specifically to physiological effects rather than the definition of hydrostatic pressure itself.