Question

A 7.5 m wide rectangular channel conveys $12m^3/s$ water with a velocity of $1.5m/s$. The specific energy of the flow is

• A. 1.78 m
• B. 1.18 m
• C. 2.18 m
• D. 2.78 m

Answer 1

The correct option is B 1.18 m


$\begin{array}{cc}Q& =12m^3/s\\ V& =1.5m/s\\ V& =\frac{Q}{A}\\ 1.5& =\frac{12}{7.5\times y}\\ y=1.067m& \\ E& =y+\frac{v^2}{2g}\\ & =1.067+\frac{{1.5}^2}{2\times 9.81}=1.18m\end{array}$