For length Meter and for time Second.
Time . . . SecondMass . . . KilogramLength . . . Meter
The principal SI units used to derive all other SI units are the base SI units. These are the units for physical quantities such as length, time, mass, electric current, temperature, amount of substance, and luminous intensity.
The base (SI) unit is meter.
"si" stands for the International System of Units, which is the modern form of the metric system. It is based on seven base units, one of which is the meter for length.
The base unit for length is the metre, the base unit for mass is the kilogram.
The SI unit for length is metre (m).The SI unit for mass is kilogram (kg).
The meter (m) is the SI base unit for the measurement of length.
In the SI, it is DEFINED as a base unit, together with the unit of length, the unit of time, and a few others. Other units are derived from these base units.
The fundamental SI units for mass, length, and time are kilograms, meters, and seconds, respectively.
In the SI, it is DEFINED as a base unit, together with the unit of length, the unit of time, and a few others. Other units are derived from these base units.
The Meter (length) and Kelvin (temperature)
In a system of units such as the SI, BASE UNITS are defined; other units are derived from those.For example, in the SI, the meter, the kilogram, and the second are base units; the units for area (meters squared), for speed and velocity (meters/second), etc. are derived from the base units. Which units are base units, and which units are derived units, really depends on how the unit is defined. For example, in the SI, pressure is a derived unit; but you can just as well invent a system in which pressure is a base unit, and some other units, that are base units in the SI, are derived in this new system.