A generator of e.m.f. 80 V has an internal resistance of 0.04 Ω. If its terminal voltage is 75 V, determine the current.
Correct answer: A. 125 A
- A. 125 A
- B. 135 A
- C. 145 A
- D. 155 A
- E. 165 A
Explanation
To determine the current, use the formula I = (E - V) / r, where E is the electromotive force (80V), V is the terminal voltage (75V), and r is the internal resistance (0.04Ω). Substitute the values into the formula to get I = (80V - 75V) / 0.04Ω = 125A. Therefore, option A is correct. All other options result from incorrect calculations based on this formula.
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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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