Internal Battery Resistance: When a 100-Ω Resistor Is Connected Across

question 32

Multiple Choice

Internal battery resistance: When a 100-Ω resistor is connected across the terminals of a battery of emf ε and internal resistance r, the battery delivers 0.794 W of power to the 100-Ω resistor. When the 100-Ω resistor is replaced by a 200-Ω resistor, the battery delivers 0.401 W of power to the 200-Ω resistor. What are the emf and internal resistance of the battery?

• A) ε = 10.0 V, r = 5.02 Ω
• B) ε = 4.50 V, r = 4.00 Ω
• C) ε = 9.00 V, r = 2.04 Ω
• D) ε = 9.00 V, r = 1.01 Ω
• E) ε = 12.0 V, r = 6.00 Ω

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