Question

Tow tanks are connected in parallel by two pipes A and B of identical friction factors and lengths. If the size of pipe A is double than that of pipe B, then their discharges will be in the ratio of

• A. 2
• B. 4
• C. 5.66
• D. 32

Answer 1

The correct option is C 5.66

The head loss in both pipes will be same and it is proportional to $\frac{Q^2}{D^5}$

$\therefore \frac{Q_1^2}{D_1^5}=\frac{Q_2^2}{D_2^5}$

$\frac{Q_1^2}{Q_2^2}={\left(\frac{D_1}{D_2}\right)}^5=2^5=32$

$\frac{Q_1}{D_2}=4\sqrt{2}=5.66$