Units, Measurements & Errors — Exam Cheat Sheet — Summary

7 SI base units: m · kg · s · A · K · mol · cd
Dim. formulas: Force [ $M^{1}$$L^{1}$$T^{-2}$ ] | Energy [ $M^{1}$$L^{2}$$T^{-2}$ ] | Pressure [ $M^{1}$$L^{-1}$$T^{-2}$ ] | Power [ $M^{1}$$L^{2}$$T^{-3}$ ] | Angular momentum [ $M^{1}$$L^{2}$$T^{-1}$ ]
Error rules: Sum/Diff → add $\Delta A$ + $\Delta B$ | Product/Quotient → add $\Delta A$ /A + $\Delta B$ /B | Power Aⁿ → n·( $\Delta A$ /A)
Sig figs: Leading zeros = never count | Trailing zeros after decimal = always count
DA limitations: Cannot find dimensionless constants; cannot distinguish same-dimension formulas