Question 13028 of 731 · Texas Journeyman Electrician Exam
Resistors of 5, 10 and 15 ohms are connected in series across 120 volts. What is the voltage across the 10 ohm resistor?
Exactly one answer is correct.
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Correct answer to question 13028
- D: 40 V
Explanation
Total resistance is 30 ohms, so I = 120 / 30 = 4 A, and the drop across 10 ohms is 4 x 10 = 40 V. In a series circuit the source voltage divides in proportion to resistance; 120 V would only appear across a parallel branch.
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