A 12 V source is connected across a 4 ohm resistor. What current flows?
Answer and explanation
Correct answer: C. 3 A, from I = V/R = 12/4
- Step 1: Ohm's law: V = I R, so I = V/R. Step 2. I = 12/4 = 3 A. Answer: 3 A. Why not the others: Multiplying, inverting or subtracting breaks Ohm's law.
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