Question 13013 of 749 · Maryland Journeyperson Electrician Exam
A motor takes 20 kW of electrical input and operates at 90 % efficiency. What is its output in horsepower?
Exactly one answer is correct.
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Correct answer to question 13013
- A: 24.1 hp
Explanation
Output power is 20,000 W x 0.90 = 18,000 W, and 18,000 / 746 = 24.1 hp. Ignoring efficiency gives 26.8 hp, and dividing by the efficiency gives 29.8 hp.
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