Question

Two reservoirs are connected by two pipes P and Q. The pipes have the same diameter and length and are placed in parallel. If the friction factor of P is 9 times that of Q, then the discharge in P to that in Q is

• A. 0.5
• B. 0.45
• C. 0.33
• D. 0.27

Answer 1

The correct option is C 0.33

Pipes are placed parallel

$\therefore h_{fp}=h_{fQ}$

${\left(\frac{fL{Q}^2}{12.1D^5}\right)}_P={\left(\frac{fL{Q}^2}{12.1D^5}\right)}_Q$

$9f{Q}_P^2=f.Q_Q^2$

$Q_P=\frac{Q_Q}{3}=0.33Q_Q$