Series circuit: A circuit where components are connected in a single loop — there is only one path for current to flow.
Parallel circuit: A circuit where components are connected on separate branches — there are multiple paths for current to flow.
Junction: A point in a circuit where the wire splits into two or more branches. Current divides at a junction.
Total resistance (series): Rtotal = R₁ + R₂ + R₃ — resistances simply add.
Total resistance (parallel): 1/Rtotal = 1/R₁ + 1/R₂ — always less than the smallest individual resistance.
This definitions covers Key Definitions within Series & Parallel Circuits for GCSE Physics. Revise Series & Parallel Circuits in Electricity for GCSE Physics with 20 exam-style questions and 30 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 10 of 16 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Practice questions for Series & Parallel Circuits
In a series circuit, what is true about the current at all points?
A student adds an extra lamp to a parallel circuit. Explain how this affects the total current from the supply and the brightness of the original lamps.