NumericalModerate1 mark
2(iii)
In the below circuit diagram, calculate:
the current I.
Topic: Current, resistance and circuits
Previous-year question practice database
Answer
Exam answer
The main current divides between the two parallel branches, so I = I₁ + I₂
I = 0.4 + 0.6 = 1.0 A
Current I = 1.0 A
Explanation
At a junction, the current arriving equals the total current leaving — that is Kirchhoff's first rule, and here it simply means the two branch currents add up to the main one.
This also gives you a free check on part (b). Work out the total current independently — V across the parallel part is 4.8 V, so I = 4.8 ÷ 4.8 = 1.0 A — and it agrees. Whenever a question gives you the pieces AND the whole, check them against each other before you move on.
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