Pressure is the magnitude of the force applied perpendicular to the surface of an object per unit area over which that force is distributed. It is the ratio of the force distributed over a specific surface area. Pressure can be measured using any units of force and area. The international standard unit for pressure is the Pascal (Pa), which is one Newton per square meter.
The mathematical formula for pressure (symbolized as p) is:
p = 𝐹 / 𝐴
where 𝑝 is the pressure, 𝐹 is the normal force, and 𝐴 is the area of contact.
Absolute pressure is the sum of the gauge pressure (also known as relative pressure) and the atmospheric pressure at a specific location. In everyday life, pressure measurements, such as tire pressure and blood pressure, typically refer to gauge pressure.
For more information on the impact force and pressure distribution of nozzle sprays, please refer to:
Nozzle Dynamics: Impact Force and Pressure Distribution