Physics A-Level
Base units
What Base units means in Physics A-Level, as defined for AQA, OCR.
Definitions of Base units
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Reference: OCR
Each of the seven S.I. base quantities has its own base unit, and derived units are built from these.
The kilogram (kg) is the base unit of mass and the metre (m) is the base unit of length.
The metre (m) is the base unit of length and the second (s) is the base unit of time.
The seven units kg, m, s, A, K, mol and cd from which an SI unit is built.
Topics that use Base units
- Use of SI units and their prefixes (AQA A-Level)
- S.I. units (OCR A-Level)
Related terms
- Dimensional analysis
- S.I. base quantities
- Unit conversion
- Avogadro constant
- Derived units
- Mass and the kilogram
- Molar calculations
- Prefixes and unit conversion
Using Base units in the exam
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