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SI units
Explore si units within quantities and units. Express physical quantities in consistent units. Check that both sides of an equation describe the same kind of quantity before substituting values.
Specification outcomes (6)
- 2.1.2(a) Système Internationale (S.I.) base quantities and their units – mass (kg), length (m), time (s), current (A), temperature (K), amount of substance (mol).
- 2.1.2(b) Derived units of S.I. base units, such as momentum (kg m s⁻¹) and density (kg m⁻³).
- 2.1.2(c) Recognise and use units listed in this specification.
- 2.1.2(d) Check the homogeneity of physical equations using S.I. base units.
- 2.1.2(e) Use prefixes and their symbols to indicate decimal submultiples or multiples of units (pico, nano, micro, milli, centi, deci, kilo, mega, giga, tera).
- 2.1.2(f) Apply conventions for labelling graph axes and table columns, for example speed / m s⁻¹.
H156 v2.0 · May 2026
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