If r = 0, R = ∞, (V = ε - Ir) then:
Correct answer: B. V = ε
- A. V > ε
- B. V = ε
- C. V < ε
- D. V = 0
Explanation
The equation V = ε - Ir describes the terminal voltage. If the internal resistance (r) is zero, the term Ir becomes zero, regardless of the current. This simplifies the equation to V = ε, meaning the terminal voltage is equal to the EMF.
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About Current Electricity
Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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