A device on a 220 V supply draws 2 A. What is its power?
Answer and explanation
Correct answer: B. 440 W
- Step 1: Power P = VI. Step 2. P = 220 × 2 = 440 W. Answer: 440 W. Why not the others: 110 W is what you get if you divide V by I. 222 W is what you get if you add the numbers. 880 W is what you get if you square the current.
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