Question

A rectangular weir is installed in a gully to measure runoff. The length of weir crest is \(3 \, \text{m}\) and the head of water over the weir is \(40 \, \text{cm}\). Find the discharge through weir. Take the value of coefficient of discharge (\(C_d\)) as \(0.60\).

• A. \(1.07 \, \text{m}^3/\text{sec}\)
• B. \(1.34 \, \text{m}^3/\text{sec}\)
• C. \(0.45 \, \text{m}^3/\text{sec}\)
• D. \(4.22 \, \text{m}^3/\text{sec}\)

Hint:

For a rectangular sharp crested weir: \[ \boxed{ Q = \frac{2}{3} C_d L \sqrt{2g} H^{3/2} } \] Discharge varies directly with:
• Crest length \(L\)
• Head raised to power \(3/2\)

Answer 1

The Correct Option is B