# Physics Topic: Measurements

Recall the following base quantities and their units: mass (kg), length (m), time (s), current (A), temperature (K), amount of substance (mol).

Express derived units as products or quotients of the base units and use the named units listed in ‘Summary of Key Quantities, Symbols and Units’ as appropriate.

Show an understanding of and use the conventions for labeling graph axes and table columns as set out in the ASE publication SI Units, Signs, Symbols and Abbreviations, except where these have been superceded by Signs, Symbols and Systematics (The ASE Companion to 5-16 Science, 1995).

Use the following prefixes and their symbols to indicate decimal sub-multiples or multiples of both base and derived units: pico (p), nano (n), micro, milli (m), centi (c), deci (d), kilo (k), mega (M), giga (G), tera (T).

Make reasonable estimates of physical quantities included within the syllabus.

Show an understanding of the distinction between systematic errors (including zero errors) and random errors.

Show an understanding of the distinction between precision and accuracy.

Assess the uncertainty in a derived quantity by simple addition of actual, fractional or percentage uncertainties. (A rigorous statistical treatment is not required.)

Distinguish between vector and scalar quantities and give examples of each.

Add and subtract coplanar vectors.

Represent a vector as two perpendicular components.