SI Units for Physical Quantities

SI units give a standard way to measure physical quantities. A physical quantity can be defined by how it is measured or by how it is calculated from other measurements. For example, the mass and dimensions of a metallic cube can be found with a weighing machine and a meter scale.

Some quantities...

A physical quantity is any number that describes a physical phenomenon quantitatively. For instance, length is a physical quantity that describes the distance between two points.

The measurements of physical quantities are expressed in terms of units. The mass of your body can be expressed in kilograms and your height in terms of meters.<...