Quick Recap — Derived Units, Prefixes & More Dimensions

A short refresher for this set.

Common derived SI units

Quantity Unit In base units
Force newton (N) kg m s−2^{-2}
Energy joule (J) kg m2^2 s−2^{-2}
Power watt (W) kg m2^2 s−3^{-3}
Frequency hertz (Hz) s−1^{-1}
Charge coulomb (C) A s

Metric prefixes

Prefix Factor Prefix Factor
nano 10−910^{-9} kilo 10310^{3}
micro 10−610^{-6} mega 10610^{6}
milli 10−310^{-3} giga 10910^{9}
centi 10−210^{-2} tera 101210^{12}

A few more dimensions

Area [L2][L^2], Volume [L3][L^3], Impulse [MLT−1][MLT^{-1}], Charge [AT][AT]. Plane angle (radian) and solid angle (steradian) are dimensionless. Length units: 1 Å =10−10= 10^{-10} m, and a light year measures distance, not time.