Electricity

Microscopic origin of current in terms of electron drift.

Linear V–I relation; resistance depends on geometry and resistivity.

Linear approximation R = R₀(1 + αΔT) and the colour code.

Distinction between EMF and terminal voltage under load.

Combination rules for resistor networks.

Current law (KCL) and voltage law (KVL) for circuit analysis.

Using two resistors to split a supply voltage and obtain a specific output voltage.

Null-method comparison; balanced-bridge condition.