Enter the density, depth, and total surface area into the calculator to determine the hydrostatic force.

Hydrostatic Force Formula

The following formula is used to calculate a hydrostatic force. 

Hf =  (ρ * g * h - p0) * A
  • Where Hf is the hydrostatic force (N, newtons)
  •  ρ is the density of the fluid (1000kg/m^3)
  • g is the acceleration due to gravity (9.81 m/s^2)
  • h is the depth (m)
  • p0 is atmospheric pressure (101,325 pascals)
  • A is the total area (m^2)

To calculate the hydro-static force, multiply the density, depth, and acceleration due to gravity together, subtract the atmospheric pressure, then multiply this result by the area.

What is Hydrostatic Force?

Definition:

A hydrostatic force, also commonly referred to as the buoyant force, is a measure of the force acting on an object that is submerged underwater that arises from the differences in pressure between the water and the atmosphere above it.

How to calculate hydrostatic force?

Example:

The following example outlines the steps needed to calculate a hydrostatic force.

First, determine the density of the fluid. We are assuming freshwater for this example so the density is 1000kg/m^3.

Next, determine the depth of the object. In this case, the object is at a depth of 100 meters.

Next, determine the surface area of the object. In this problem, the surface area is calculated to be 10m^2

Finally, calculate the hydrostatic pressure using the formula above:

Hf =  (ρ * g * h + p0) * A

Hf =  (1000 * 9.81 * 100 + 101325) * 10

Hf =  10,823,250 N