A scuba diver descends into the ocean, experiencing an increase in pressure. Based on the principles of hydrostatic equilibrium, what can the diver expect regarding the pressure change with depth?

When a diver goes deeper, the weight of the water above them pushes harder on the body, so pressure rises. Hydrostatic equilibrium tells us that the pressure gradient is the weight of the column of water per unit area, giving the formula \(p = p_0 + \rho g h\). This means pressure increases roughly linearly with depth, about one atmosphere for every ten meters of water. For example, at 30 m the diver feels about four atmospheres of pressure, because \(3 \text{ atm}\) of water plus the atmospheric pressure at the surface. Thus the diver can expect a steady, proportional rise in pressure as they descend.