Resistors of 4 Ω and 12 Ω are in parallel across 12 V. What is the total current?
Answer and explanation
Correct answer: A. 4 A
- Step 1: Parallel resistance: 1/R = 1/4 + 1/12 = 1/3, so R = 3 Ω. Step 2. I = 12/3 = 4. Answer: 4 A. Why not the others: 0.75 inverts; 1 A and 3 A are the branch currents of 12 Ω and 4 Ω.
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