Practice Question: Reynolds Number of a Closed Pipe

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Solution

Answer: D) 2,800,000

Reynolds Number is calculated as follows:
\[Re= \frac{vD}{\vartheta \\}\]
Flow Velocity:
\[v=30 ft/s\]
Pipe diameter:
\[D = 1\ ft\]


Kinematic Viscosity of Water at 70 \(\mathtt{{}^\circ\ \!{F}}\):
\[\vartheta=1.059×10^{-5} ft^2/sec\]
Reynolds Number:
\[Re= \frac{30 ft/s× 1 \ ft}{1.059×10^{-5}  ft^2/sec}\]

\[Re=2,832,861≈2,800,000\]
 

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