In a reach of open channel flow with discharge Q = 10 m3/s, the depth of flow at section A is 1.5 m and at section B it is 1.6 m. The difference in specific energy at two sections can be accordingly taken as 0.09 m. The bed slope is 1 in 2000. The mean energy slope between the sections is given as 0.003. What is the length of reach AB?
1
54 m with A on upstream
2
54 m with B on upstream
3
36 m with A on Upstream
4
36 m with B on upstream