S.I. base quantities
What S.I. base quantities means in Physics A-Level, as defined for AQA, OCR.
Definitions of S.I. base quantities
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Reference: AQA
Mass, length, time, amount of substance, thermodynamic temperature and electric current, each with its associated SI unit.
The Système Internationale defines seven base quantities, each with its own base unit, and mass is one of them.
Mass and length are listed as S.I. base quantities, with length measuring the separation between two points.
Length and time are S.I. base quantities, with time measuring duration.
Topics that use S.I. base quantities
- Use of SI units and their prefixes (AQA A-Level)
- S.I. units (OCR A-Level)
Related terms
- Base units
- Dimensional analysis
- Unit conversion
- Avogadro constant
- Derived units
- Mass and the kilogram
- Molar calculations
- Prefixes and unit conversion
Using S.I. base quantities in the exam
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