Three identical 2 ohm resistors are connected in series to a 12 V supply. What is the current?
Answer and explanation
Correct answer: B. 2 A
- Step 1: Total resistance = 2 + 2 + 2 = 6 ohms. Step 2. I = V/R = 12/6 = 2 A. Answer: 2 A. Why not the others: 6 A: That uses a single resistor only. 24 A: That multiplies 12 V by 2 ohms. 0.5 A: That inverts the ratio of voltage to resistance.
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