Question

Determine the pressure, in psia, 60 ft below the surface of the sea. (The specific gravity of the sea is 1.022)

Answer 1

The pressure is given as follows:

$$p = \rho g h$$

where $\rho = 1022kg/m^3$ is the specific gravity of the seawater, $g = 9.81m/s^2$ is the gravitational acceleration, and $h = 60ft\approx 18.29m$ is the depth. Thus, obtain:

$$p = 1022\cdot 9.81\cdot 18.29 \approx 1.834\times 10^5Pa$$

In psia:

$$p_a = p/6895 + 14.7psi\approx 41.29psia$$

where 14.7psi is the atmospheric pressure.

Answer. 41.29 psia.