The pressure is defined as the force acting per unit area. The pressure is thrust per unit area, hence it is directly proportional to thrust and inversely proportional to area.
The units used for pressure is pounds per square inch, Newtons per square meter, or Pascals. Atmosphere, bar, torr, and meters seawater are the other units that are used for expressing pressure.
Pascal is the SI unit of pressure and it is a derived unit. Following is the equation that is used for expressing pressure:
- P is the pressure
- F is the force acting per unit area
- A is the unit area
Types of pressure
Following are the different types of pressure based on the reference pressure:
- Absolute pressure: Pressure that is related to reference pressure is known as absolute pressure.
- Differential pressure: The difference between the two pressures is equal to the differential pressure.
- Atmospheric pressure: Pressure related to the atmosphere that surrounds the earth is atmospheric pressure. This pressure is weather-dependent.
- Gauge pressure: This is the difference between absolute pressure and atmospheric pressure.