You are given four bulbs of 25W, 40W, 50W, and 60W, which are connected in a parallel combination. Which bulb has the lowest resistance?
Correct answer: B. 60 W
- A. 25 W
- B. 60 W
- C. 50 W
- D. 40 W
Explanation
All bulbs are designed for the same voltage (like in a standard household), and resistance is R = V²/P. Since voltage is constant, resistance is inversely proportional to power. The bulb with the highest power rating (60W) will have the lowest resistance.
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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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