K326 / K327 / 2027

Chapter 13

D.C. circuits

The connections determine which current and voltage relationships apply.

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

Circuit symbols, series and parallel relationships, complete circuits and measurements. For K326 / K327 (2027) / 5086 / 5087 (2026).

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  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.