Basiseenheden en afgeleide eenheden

Physical quantities can be divided into base quantities and derived quantities. Base quantities can be expressed through a measurement process, and their units are known as base units.

For example, the distance between two points is measured in terms of meters. Here the base quantity is the distance, and the unit used to measure it is the meter, which is the base unit.

The physical quantities obtained from the combinations of base quantities are known as derived quantities, and the units used to define these quantities are known as derived units.

For example, the speed of a moving car from one point to another is defined as the distance traveled divided by travel time. Here, speed is a derived quantity obtained from the base quantities distance and time.

The unit of speed is meters per second, the derived unit from the base units, meters, and seconds. All the derived quantities and derived units are defined from base quantities and base units, respectively.