A 12 V battery is connected across a 4 ohm resistor and a 2 ohm resistor in series. What is the current?
Answer and explanation
Correct answer: D. 2 A
- Step 1: Total resistance = 4 + 2 = 6 ohms. Step 2. I = V/R = 12/6 = 2 A. Answer: 2 A. Why not the others: 3 A: That uses only the 4 ohm resistor. 6 A: That uses only the 2 ohm resistor. 1 A: That adds the resistors and divides incorrectly.
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