Depth and vertex angle of triangular channel for minimum perimeter

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A triangular shaped channel is to be designed to carry 700 L/s on a slope of 0.0001. Determine what vertex angle and depth of water over the vertex will be necessary to give a section with minimum perimeter, assuming the channel is made of timber, n = 0.012. Use Manning’s formula.

A.   θ = 45°, h = 1.425 m C.   θ = 45°, h = 2.125 m
B.   θ = 90°, h = 2.215 m D.   θ = 90°, h = 1.215 m


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