Engineering Board Exam Reviewer · Fluid Mechanics · hard
Water flows at 50 L/s through a 250 mm pipe 1 km long. If f = 0.025, what is the head loss?
- 5.288 m
- 5.192 m
- 21.152 m
- 1.322 m
Answer
A. 5.288 m
Solution
V = Q/A = 0.05/(π /4 × 0.252) = 1.0186 m/s. hf = 0.025(1000/0.25)(1.01862/19.62) = 5.288 m. (Equivalent: hf = 0.0826fLQ²/D⁵.)
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