What is the equation for calculating pressure at depth?

The equation for calculating pressure at depth in a fluid, such as water, is indeed based on the interplay between atmospheric pressure and the pressure exerted by the water column above a given depth. The correct formulation is as follows:

Pressure at a certain depth is determined by the sum of the atmospheric pressure (the pressure exerted by the air above the water) and the hydrostatic pressure, which is calculated using the density of the water, the acceleration due to gravity, and the depth of the water below the surface. This relationship is mathematically represented as:

Pressure (P) = Atmospheric pressure + (Density of water × Gravity × Depth)

In this equation, atmospheric pressure accounts for the pressure acting on the water's surface from the weight of the air above it. The term (Density of water × Gravity × Depth) quantifies the additional pressure that is created by the weight of the water column itself as you go deeper. Since water is incompressible, this pressure increases linearly with depth.

This understanding of pressure relative to depth is crucial for divers, as it helps them anticipate how pressure changes during descents and ascents, ensuring safe diving practices.