Forces: Fluid Pressure

Fluid Pressure

Fluid Pressure can be explained as the force per unit area applied by a fluid when it’s in a state of rest.
Fluids include both liquids and gases, and both increase pressure with depth.
Fluid pressure can be found in all directions, not just down. This is why you can feel water pressure on all sides when you dive into a pool.

The formula to find fluid pressure is pressure = height of column x density of liquid x gravity.
Remember the unit for pressure is Pascal (Pa), the unit for density is kilograms per cubic metre (kg/m³), and gravity is approximately 9.8 m/s².
Using this formula you can calculate the pressure at any depth in a stationary fluid.

Atmospheric pressure, also known as air pressure, is the pressure within the atmosphere of Earth.
Air pressure decreases as altitude increases.
The lower pressure at higher altitudes can impact physical abilities, e.g. athletes may struggle to breathe and perform at their peak.
Common instruments for measuring air pressure include barometers and manometers.

Pascal’s Principle states that the pressure applied at any point in a fluid in a confined space is transmitted equally in all directions.
This principle is essential in hydraulic systems where a small force applied to a small area can generate a large force over a larger area.
This principle is used in several real-life applications like hydraulic lifts in car garages, hydraulic brakes in vehicles, and even in various heavy machinery machinery.