Electric circuits: Charge, current, potential difference, Ohm's Law, ohmic and non-ohmic devices, and series and parallel circuits

What this note covers

1. Why circuits live inside Criterion 6, and the limits the course sets
2. Charge and current: I = q/Δt and counting electrons
3. Potential difference, energy and Ohm's Law
4. Ohmic and non-ohmic components: reading V-I graphs
5. Series and parallel circuits: the rules and where they come from
6. Circuit diagrams, meters, and household energy in kilowatt-hours
7. How this topic is examined in Section C, and what separates a top answer

7 sections · 12 key terms & formulas · 6 common mistakes