An electrical bulb marked 100 W, 200 V would mean the resistance is:
Correct answer: C. 400 ohm
- A. 200-ohm
- B. 50 ohm
- C. 400 ohm
- D. 5 ohm
Explanation
From the power formula P = V²/R, we can solve for resistance: R = V²/P. R = (200 V)² / 100 W = 40000 / 100 = 400 Ω.
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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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