For a triangular channel of side slope 2 horizontal : 1 vertical, the froude number is given by Fr.
1
\(\frac{{{\rm{V}}\sqrt 2 }}{{\sqrt {{\rm{gy}}} }}\)
2
\(\frac{{\rm{V}}}{{\sqrt {{\rm{2gy}}} }}\)
3
\(\frac{{{\rm{V}}\sqrt 2 }}{{{\rm{gy}}}}\)
4
\(\frac{{\rm{V}}}{{\sqrt {{\rm{gy}}} }}\)