What is most economical channel section ? Write conditions for rectangular channel section to be economical .

What is most economical channel section ? Write conditions for rectangular channel section to be economical . 
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1 Answer

Answer :

Most Economical Channel Section: - A channel which gives max. discharge for a given c/s area & bed slope and coefficient of roughness is called as Most Economical Channel Section.

OR

The most economical channel section is the one which gives maximum discharge for a given amount of excavation.

Condition for rectangular channel: - i) b = 2d ii) R = d/2
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channel is said to be of most economical cross-section, if (A) It gives maximum discharge for a given cross-sectional area and bed slope (B) It has minimum wetted perimeter (C) It involves lesser excavation for the designed amount of discharge (D) All of the above

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