A light bulb rated as 60 W at 220 V has a potential difference of 110 V across its ends, The power dissipated in this light bulb is:
- A. 30 W
- B. 45 W
- C. 15 W ✓
- D. 2 W
Correct Answer: C. 15 W
Explanation
Power is proportional to the square of voltage (P \propto V^{2}). Since voltage is halved (110V instead of 220V), power becomes one-fourth: 60/4 = 15 W.
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