Question 13004 of 731 · Texas Journeyman Electrician Exam
A heater rated 4,000 watts at 240 volts is connected to a 208 volt supply. Assuming constant resistance, about how much power will it produce?
Exactly one answer is correct.
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Correct answer to question 13004
- D: 3,004 W
Explanation
Power varies with the square of voltage at constant resistance: P = 4,000 x (208 / 240) squared = about 3,004 W. Scaling only linearly by 208 / 240 gives the common wrong answer of 3,467 W.
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