At a junction, flows in. Two branches carry and away, and a third branch carries the rest. What is the current in the third branch?
Answer and explanation
Correct answer: C.
- Step 1: Charge is conserved: current in equals current out.
- Step 2: , so A.
Answer
.
Why not the others: : adds the two known currents. : adds all the currents including the one entering. : subtracts only one of the known branch currents.
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