Question 9032 of 234 · California Wastewater Operator Exam
A pump delivers 500 gpm against a total dynamic head of 60 ft. Pump efficiency is 70 percent. What is the brake horsepower? (1 hp = 3,960 gpm-ft)
Exactly one answer is correct.
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Correct answer to question 9032
- A: 10.8 hp
Explanation
Water horsepower = 500 x 60 / 3,960 = 7.6 hp. Brake horsepower = water horsepower / efficiency = 7.6 / 0.70 = 10.8 hp. Multiplying by the efficiency is the usual error.
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