A cell of emf 12 V and internal resistance 4 ohm is connected to an external resistor of 2 ohm. What current flows?
Answer and explanation
Correct answer: A. 2 A
- Step 1: The current is A. Answer: 2 A. Why not the others: 6 A: ignores the internal resistance. 3 A: uses the internal resistance only. 72 A: multiplies instead of dividing.
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