what is a base SI unit
SI base unit
The seven SI base units and the interdependency of their definitions: for example, to extract the definition of the metre from the speed of light , the definition of the second must be known while the ampere and candela are both dependent on the definition of energy which in turn is defined in terms of length , mass and time .
International System of Units SI base unit 2019 redefinition of the SI base units History of the metric system Metrology Metre Convention Metric system Thermodynamic temperature Alternative approaches to redefining the kilogram Mole (unit) Dalton (unit) International Prototype of the Kilogram Kelvin Metre Kilogram Carlos Ibáñez e Ibáñez de Ibero Caesium standard Temperature Dimensional analysis Measurement Centimetre–gram–second system of units Base unit of measurement Speed of light National Physical Laboratory of India General Conference on Weights and Measures Planck units Ampere Metrication in the United Kingdom Ohm Metrication Planck constant Candela Imperial and US customary measurement systems Physical constant Metrication in the United States History of the metre Unit of measurement Vacuum permeability Entropy Boltzmann constant Gas constant Radian Kibble balance Avogadro constant Magnetic field Mass Coherence (units of measurement) History of chemistry System of units of measurement Celsius International System of Electrical and Magnetic Units Second Planck's law History of electromagnetic theory Viscosity Elementary charge Field electron emission Gaussian units Vacuum permittivity List of unusual units of measurement Specific heat capacity Astronomical unit Weight Pound (mass) Magnetic flux quantum Time-variation of fundamental constants Zero-point energy Heat Metric prefix Time in physics MKS system of units Litre Sievert Iridium Development communication Buckingham π theorem Time Second law of thermodynamics Stefan–Boltzmann law Volt Hartree atomic units Maxwell's equations Spacetime Roentgen (unit) Equipartition theorem Electric current Thermal conductivity and resistivity Stefan–Boltzmann constant Scale of temperature Molar mass constant Gas First law of thermodynamics Binary prefix Physical quantity Viscosity models for mixtures Electronvolt History of physics Ising model Force Magnetic sail Tartan Van der Waals equation Imperial units Exergy 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