Chapter 12
Electric charge and current of electricity
Current describes charge passing a point; voltage describes energy transferred per charge.
Choose the correct quantities and measurement points before calculating.
Includes charge interactions, current, e.m.f., potential difference and wire resistance. For K326 / K327 (2027) / 5086 / 5087 (2026).
Choose a topic
Electric charge and interactions
Distinguish positive, negative and neutral objects, and interpret attraction and repulsion.
Current, charge and electron flow
Use charge per second, distinguish flow directions and measure current in the chosen branch.
E.m.f. and potential difference
Distinguish source e.m.f. from component potential difference and connect a voltmeter across the intended points.
Resistance and wire dimensions
Match voltage and current to the same component, then compare wire length and cross-sectional area.