Question

The circular water pipes shown in the sketch are flowing full. The velocity of flow (in m/s) in the branch pipe "R" is

• A. 3
• B. 4
• C. 5
• D. 6

Answer 1

The correct option is B 4


$Q_1=Q_2+Q_3$
$\Rightarrow A_1{V}_1=A_2{V}_2+A_3{V}_3$
$\Rightarrow \frac{\pi }{4}(4{)}^2\times 6=\frac{\pi }{4}(4{)}^2\times 5+\frac{\pi }{4}(2{)}^2\times V_3$
$\Rightarrow 16\times 6=16\times 5+4V_3$
$\Rightarrow 16=4V_3$
$\Rightarrow V_3=4m/s$
$\therefore V=4m/s$