What is the standard unit of pressure in the SI system?

The standard unit of pressure in the SI (International System of Units) system is the Pascal (Pa). This unit is defined as one newton per square meter, which provides a clear and direct relationship between force and area, making it an essential measure in physics and engineering.

The Pascal is widely used in scientific disciplines and engineering applications to represent pressure, reflecting its fundamental nature and origin based on the basic SI units of force and area. Thus, when measuring pressure in terms of the standard system, the Pascal is the most appropriate unit, aligning with the international agreement on units of measure.

Atmosphere (atm), pound per square inch (psi), and bar, while commonly used in various applications and industries, do not represent the standard unit as defined by the SI system. They might be used for practical measurements or specific contexts, but they require conversion to Pascal when considering standardization in scientific work.