← Physics syllabus

SingaporePhysics

Measurement

6 dot points across 6 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How do the uncertainties in measured quantities combine when those quantities are added, multiplied or raised to a power?

Combine uncertainties in derived quantities by adding absolute uncertainties for sums and differences and adding fractional uncertainties for products, quotients and powers
A focused answer to the H2 Physics Measurement learning outcome on propagating uncertainty. Adding absolute uncertainties for sums and differences, adding fractional uncertainties for products and quotients, and handling powers.
8 min answer →

How do random and systematic errors affect a measurement, and how do precision and accuracy describe the quality of data?

Distinguish random and systematic errors, relate them to precision and accuracy, and quote results to an appropriate number of significant figures with an estimated uncertainty
A focused answer to the H2 Physics Measurement learning outcome on errors. Random versus systematic errors, the link to precision and accuracy, and how to quote a measurement with an uncertainty and sensible significant figures.
8 min answer →

How do we linearise a physical relationship so that a straight-line graph yields the quantities we want from its gradient and intercept?

Rearrange a physical relationship into straight-line form y = mx + c, plot the appropriate variables, and extract physical quantities from the gradient and intercept
A focused answer to the H2 Physics Measurement learning outcome on graphical analysis. Linearising relationships into y = mx + c form, choosing axes, and reading physical quantities from gradient and intercept in Paper 3 and Paper 4.
8 min answer →

How do SI prefixes and order-of-magnitude reasoning let us handle quantities spanning more than forty powers of ten?

Use SI prefixes from pico to tera, convert between prefixed units consistently, and make order-of-magnitude estimates to check whether a numerical answer is physically reasonable
A focused answer to the H2 Physics Measurement learning outcome on prefixes and estimation. The common SI prefixes, how to convert safely between them, and how order-of-magnitude estimates catch unreasonable answers.
7 min answer →

How do we distinguish scalars from vectors, and how do we add and resolve vectors to solve physical problems?

Distinguish scalar and vector quantities, add coplanar vectors, and resolve a vector into perpendicular components
A focused answer to the H2 Physics Measurement learning outcome on scalars and vectors. The distinction, vector addition by the parallelogram and triangle rules, and resolving a vector into perpendicular components.
8 min answer →

How do the seven SI base quantities and their units provide a consistent foundation for every physical measurement?

Recall the SI base quantities and their units, express derived units as products or quotients of base units, and use base units to check the homogeneity of physical equations
A focused answer to the H2 Physics Measurement learning outcome on SI base quantities and units. The seven base quantities, how derived units are built from them, and how to check an equation for homogeneity using base units.
8 min answer →