Question 13043 of 790 · California General Electrician Exam
In the common voltage drop formula VD = 2KIL / CM, what K value is normally used for aluminum conductors?
Exactly one answer is correct.
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Correct answer to question 13043
- C: 21.2
Explanation
K represents the resistance of a one circular mil, one foot conductor at operating temperature: about 12.9 ohms for copper and 21.2 ohms for aluminum. Aluminum has a higher K because it is a poorer conductor than copper.
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