A cell has emf 12.0 V. When it supplies 2.0 A the terminal pd is 11.2 V. What is its internal resistance?
Answer and explanation
Correct answer: C. 0.40 ohm
- Step 1: Lost volts V. Step 2. ohm. Answer: 0.40 ohm. Why not the others: 5.6 ohm is the load resistance ; 6.0 ohm is ; 0.80 ohm is the lost volts without dividing by the current.
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