-
The flow rate in a wide rectangular open channel is 2.0 m³ /s per metre width. The channel bed slope is 0.002. The Manning’s roughness coefficient is 0.012. The slope of the channel is classified as
-
- Critical
- Horizontal
- Mild
- Steep
Correct Option: D
| yc = | = |  |  | 1/3 | = 0.742 m | ||
| g | 9.81 |
| V = | R2/3S1/2(Manning’s equation) | |
| n |
| V = | |
| yn |
| ∴ q = | R2/3S1/2.yn | |
| n |
| 2 = | ×(yn)2/3 ⋅yn⋅(0.002)1/2 | |
| 0.012 |
R ≈ yn (wide channel)
∴ yn = 0.688 m.
