An AC supply has a peak voltage of 311 V. What is its rms voltage?
Answer and explanation
Correct answer: B. 220 V, the peak divided by the square root of two
- Step 1: For a sinusoid . Step 2. V. Answer: 220 V. Why not the others: 440 V multiplies by root 2; 155 V halves the peak; 311 V is the peak itself.
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