Forces: Fluid Pressure

Forces: Fluid Pressure

Fluid Pressure

Basics of 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.

Calculation of Fluid Pressure

  • 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.

The Impact of Atmospheric Pressure

  • 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

  • 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.