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प्रश्न
A light bulb is rated at 100 W for a 220 V a.c. supply. Calculate the resistance of the bulb.
उत्तर
Power of the bulb, P = 100 W and Voltage, V = 220 V
The resistance of the byb is fiven as `R =V^2/P = 220^2/100 = 484Ω`
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