What is the SI unit of Pressure or Stress?
Pressure Pressure is distributed to solid boundaries or across arbitrary sections of fluid "normal to" these boundaries or sections at every point. It is a fundamental parameter in thermodynamics, and it is conjugate to volume. The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N/m, or kg·m·s). This name for the unit was added in 1971; before that, pressure in SI was expressed simply in newtons per square metre. Other units of pressure, such as pounds per square inch and bar, are also in common use. The CGS unit of pressure is the barye
SI derived unit SI derived unit SI derived units are units of measurement derived from the seven base units specified by the International System of Units (SI). They are either dimensionless or can be expressed as a product of one or more of the base units, possibly scaled by an appropriate power of exponentiation. The SI has special names for 22 of these derived units (for example, hertz, the SI unit of measurement of frequency), but the rest merely reflect their derivation: for example, the square metre (m), the SI derived unit of area; and the kilogram per cubic metre (kg/m or kg