Pressure and Pressure Gauges

Abstract

Pressure may be defined as force acting against a given area. Basically there exist two types of units for measuring pressure. Pressure may be expressed as weight per unit area or as the height of a liquid column. The first alternative clearly adheres to the definition according to which a weight (force) acts against a certain area. In the English system the unit of area is usually the “square inch” with the pound as weight unit (pounds per square inch — psi). In the metric system, the square centimeter is the most common unit of area with the kilogram (kg) as weight unit (kilograms per square centimeter — kg/cm²).