In an open channel flow, the discharge at a certain section can be measured by the use of the weir, given by the equation: $Q = \frac{8}{15}C \sqrt{2g} ~ \tan (\frac{1}{2}\theta) ~ H^{5/2}$

In an open channel flow, the discharge at a certain section can be measured by the use of the weir, given by the equation:
 

where Q is the discharge, C is the coefficient of discharge, H is the head, g is gravitational acceleration. This formula is for: