Circuit Models and Current Flow

The Unipolar (Sink) Model: The belief that electricity only needs one wire to flow from the battery to a bulb. The second wire is seen as unnecessary or just a “safety” return.

The Clashing Currents Model: The idea that “positive electricity” leaves one terminal and “negative electricity” leaves the other; they meet at the bulb and “clash” to produce light.

The Attenuation (Consumed) Model: Perhaps the most common; the belief that current is “used up” by components. Students think there is more current before a bulb than after it.

The Shared Current Model: The idea that current is shared equally among components (like bulbs in a series), but some is still “lost” or used up before it gets back to the battery.

Sequential Reasoning: Thinking that a change made in a circuit only affects things “downstream” from that point, rather than the circuit as a whole system.