Worked Example: Mixed Circuit

Part of Series & Parallel Circuits · Section 7 of 16

DiagramUnit: ElectricityGCSE

PROBLEM: Find total resistance and current from a 12 V supply

Circuit: Two 6Ω resistors in parallel, connected in series with a 4Ω resistor

STEP 1: Find parallel resistance

Two 6Ω in parallel: R = (6 × 6)/(6 + 6) = 36/12 = 3Ω

STEP 2: Add series resistance

R_total = 3Ω + 4Ω = 7Ω

STEP 3: Find current (Ohm's Law)

I = V/R = 12/7 = 1.71 A (throughout the circuit)

This diagram covers Worked Example: Mixed Circuit 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 7 of 16 in this topic. Focus on the labels, the relationships between parts, and the explanation that turns the diagram into an exam-ready answer.

Practice questions for Series & Parallel Circuits

In a series circuit, what is true about the current at all points?

A. The current is the same at all points
B. The current decreases after each component
C. The current is largest near the positive terminal
D. The current splits at each component

1 markfoundation

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.

2 marksstandard

Quick recall flashcards

Current in series circuits?

SAME everywhere (I₁ = I₂ = I₃) — only one path for current

Voltage in series circuits?

ADD UP to equal supply voltage (V_supply = V₁ + V₂ + V₃)

Parallel Resistance Shortcut (Two Resistors)

How It Works: Kirchhoff's Laws (The Rules Behind the Rules)

20 questions on Series & Parallel Circuits: practise free

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