Question

The discharge passing over an ogee spillway, per unit length of its apex line is proportional to (Where H is head over the apex of its crest):
1. H
2. H2
3. H ^0.5
4. H ^1.5

Answer 1

Correct Answer - Option 4 : H ^1.5

Concept:

Discharge over an Ogee spillway is given by:

\(Q = \;\frac{2}{3}{C_d}\sqrt {2g} LH_e^{\frac{3}{2}}\)

He = Total head upstream of the crest.

L = crest width

Cd = coefficient of discharge

C = constant, which is equal to \(\frac{2}{3}{C_d}\sqrt {2g}\)<!--[if gte msEquation 12]> ^H32<![endif]--><!--[if !msEquation]-->

∴ Discharge Q is proportional to H^1.5<!--[endif]-->