Basisgrößen

Basisgrößen, also known as base quantities, are a fundamental set of physical quantities from which all other physical quantities in a system can be derived. These quantities are considered independent of each other. The most widely recognized system of basisgrößen is that of the International System of Units (SI).

The SI currently defines seven basisgrößen. These are the length, the mass, the time, the electric current, the thermodynamic temperature, the amount of substance, and the luminous intensity. Each of these basisgrößen has an associated SI base unit: the meter (m) for length, the kilogram (kg) for mass, the second (s) for time, the ampere (A) for electric current, the kelvin (K) for thermodynamic temperature, the mole (mol) for amount of substance, and the candela (cd) for luminous intensity.

The concept of basisgrößen is crucial for the logical structure of physics and metrology. By defining a minimal set of independent quantities and their units, a consistent framework for measurement and for the definition of derived quantities is established. For example, velocity is a derived quantity, defined as length divided by time. Its unit, the meter per second (m/s), is derived from the base units of length and time. Historically, the number and choice of basisgrößen have evolved as scientific understanding and measurement capabilities have advanced.