lesson
Charge flow divides at a junction
1 · Learn
In a parallel arrangement, branches connect across the same two junctions. Current entering a junction equals the total current leaving it in a steady circuit. Branch currents need not be equal if the branch components differ.
The potential difference across branches sharing the same junctions is the same in the ideal circuit model. This differs from series components sharing the supply's potential difference across a single path.
2 · Worked example
If 0.8 A reaches a junction and one branch carries 0.3 A, the other carries 0.5 A in a two-branch model.
3 · Your turn
Two branches carry 0.2 A and 0.6 A. What total current leaves when they rejoin?
Check your answer
0.8 A.
4 · Apply your learning
Annotate a supplied two-branch diagram with current arrows and check conservation at both junctions.
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Check a calculation · Year 5 onward
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Powers, roots and trigonometry · Year 7 onward
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