K223 / K224 / 2027

Chapter 11

D.C. circuits

The connections determine which current and voltage relationships apply.

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Choose a topic

  1. Circuit symbols and connections

    Draw components and identify the same connections in different layouts.

  2. Series circuits

    Explain the shared current, add voltage drops and find total resistance.

  3. Parallel circuits

    Identify equal branch voltages, add branch currents and find effective resistance.

  4. Solving a complete circuit

    Reduce a network, recover individual readings and explain what changes when a branch opens.

Syllabus coverage

This chapter covers D.C. circuits, topic 11(a-g), in the K223 / K224 syllabus (2027).

Identify shared paths and endpoints, then solve the circuit one part at a time.

Circuit symbols, series and parallel relationships, complete circuits and measurements.

View the learning outcomes
11(a)
Draw circuit diagrams using every component and source listed for this course. Circuit symbols and connections
11(b)
State and apply the equal-current rule for a series circuit. Series circuits
11(c)
State and apply the sum of series potential differences. Series circuits
11(d)
State and apply the sum of parallel branch currents. Parallel circuits
11(e)
State and apply the equal potential difference across parallel branches. Parallel circuits
11(f)
Recall and apply effective resistance for a number of resistors in series and in parallel. Series circuitsParallel circuits
11(g)
Combine current, potential difference and resistance relationships to solve a whole circuit. Solving a complete circuit