A 100 W bulb operates at 220 V. The current drawn by it is approximately: MCQ with Answer and Explanation

A 100 W bulb operates at 220 V. The current drawn by it is approximately:
A. 0.45 A
B. 0.22 A
C. 2.2 A
D. 4.5 A
Answer: Option A
Solution (By JKExamLibrary)
Electric power P = VI. Thus I = P/V = 100 W / 220 V ≈ 0.4545 A ≈ 0.45 A. This direct application of power formula is fundamental in electricity. Memory tip: 'I = P/V for resistive loads'. Competitive exams frequently test such calculations with household appliance ratings. Always use consistent units (watts, volts, amperes). Note: This assumes purely resistive load (valid for incandescent bulbs); for motors or electronics, power factor may matter, but not at this level.

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Correct Answer: Option B


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