Question 13030 of 1003 · California General Electrician Exam
A 240 volt circuit uses stranded uncoated 10 AWG copper with a DC resistance of 1.24 ohms per 1,000 feet. The run is 100 feet one way and the load is 25 A. What is the voltage drop?
Exactly one answer is correct.
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Correct answer to question 13030
- B: 6.2 V
Explanation
Total length is 200 ft, so R = 200 x 1.24 / 1,000 = 0.248 ohm and VD = 25 x 0.248 = 6.2 V. The result matches the K-factor method, 2 x 12.9 x 25 x 100 / 10,380 = 6.2 V.
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