Question 13029 of 1003 · California General Electrician Exam
A 120 volt, 2-wire branch circuit uses stranded uncoated 12 AWG copper, 150 feet one way. Using a DC resistance of 1.98 ohms per 1,000 feet, what is the voltage drop at 16 A?
Exactly one answer is correct.
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Correct answer to question 13029
- A: 9.5 V
Explanation
Total conductor length is 2 x 150 = 300 ft, so R = 300 x 1.98 / 1,000 = 0.594 ohm and VD = I x R = 16 x 0.594 = 9.5 V. Using only the one-way length gives half that value, 4.8 V.
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