Question

Specific energy of flowing water through a rectangular channel of width 5 m when discharge is 10 m³ / s and depth of water is 2 m is:
1. 1.06 m
2. 1.02 m
3. 2.05 m
4. 2.60 m

Answer 1

Correct Answer - Option 3 : 2.05 m

Concept:

The specific energy may be given as

\(E = y + \frac{{V_1^2}}{{2g}}\)

Calculation:

We know that

Q = AV

⇒ 10 = 5 × 2 × V

⇒ V = 1 m/s

\(\begin{array}{l} E = y + \frac{{V_1^2}}{{2g}}\\ E= 2 + \frac{{{{\left( {1} \right)}^2}}}{{2 \times 9.81}} = 2.05\;m \end{array}\)