A 100 W bulb operates at 200 V. Its resistance is MCQ with Answer and Explanation

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A 100 W bulb operates at 200 V. Its resistance is

A. 200 Ω

B. 400 Ω

C. 50 Ω

D. 100 Ω

Answer: Option B

Solution (By JKSSB Mock Tests)

Power P = V²/R => R = V²/P = 200²/100 = 40000/100 = 400 Ω. Also current I = P/V = 0.5 A, R = V/I = 200/0.5 = 400 Ω. Use P = V²/R for direct calculation.

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