ELECTRICAL RESISTANCE
2 marks · NormalExplain why connecting wires in a circuit are normally assumed to have zero resistance.
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Because the resistance of connecting wires is so small compared to other components in the circuit that it can usually be ignored. This simplifies calculations without appreciably affecting results.
Also accept: Wires offer very little resistance so they don’t impact current in the circuit.; The resistance is much lower than other components so it doesn’t affect the circuit significantly.
Common mistakes: saying wires have absolutely no resistance; not mentioning comparison to other components
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Marking points
B1 · 1 mark · States wires have very low resistance.
B2 · 1 mark · Explains that this can be ignored compared to other components or simplifies calculations.
Worked solution
Connecting wires are made of metals that allow charge to pass easily, so their resistance is extremely low. Compared to resistors and other components, this resistance is negligible, so we assume it is zero to make calculations easier.