A battery with internal resistance is connected to an external resistor. When current flows, the terminal voltage of the battery is
Answer and explanation
Correct answer: A. less than its emf
- Step 1: V_terminal = ε - Ir, so it is less than ε whenever I is not zero.
Answer
less than its emf.
Why not the others: equal to its emf: terminal voltage drops by Ir when current flows. greater than its emf: terminal voltage cannot exceed the emf for a discharging battery. zero: terminal voltage equals the emf minus the voltage drop over the internal resistance.
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