1.2.2—Derived units as products or quotients of the SI base units and use the

Use the defining equation to express a derived unit in base units: N=kg m s⁻², J=kg m² s⁻² and W=kg m² s⁻³.

Treat unit algebra like algebra of powers, cancel common factors and check that the final dimensions match the quantity named.

Pressure is force/area, so Pa=N m⁻²=kg m⁻¹ s⁻².

A named unit such as joule is not dimensionless; replacing it with base units exposes the physical dimensions.