A 12 V battery of internal resistance 1 ohm drives a 6 ohm and a 3 ohm resistor in parallel. What power is dissipated in the 3 ohm resistor?
Answer and explanation
Correct answer: A. 21.3 W
- Step 1: Parallel resistance is 2 ohm, so A and the terminal voltage is V. Step 2. Power in the 3 ohm resistor: W. Answer: 21.3 W. Why not the others: 10.7 W is the 6 ohm resistor; 32.0 W is the total in both; 48 W uses the full 12 V across a 3 ohm resistor.
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