For a most economical trapezoidal channel sectiona)hydraulic mean radi...
Explanation:
An economical trapezoidal channel section is one in which the cross-sectional area of the channel is minimized for a given flow rate. The hydraulic mean radius (R) is an important parameter that determines the hydraulic efficiency of a channel. It is defined as the ratio of the cross-sectional area of the flow to the wetted perimeter.
R = A/P
where A is the cross-sectional area and P is the wetted perimeter.
For an economical trapezoidal channel section, the hydraulic mean radius equals half the depth of flow. This is because a trapezoidal channel with this proportion has the minimum wetted perimeter for a given cross-sectional area, which results in a lower energy loss due to friction.
Therefore, option B is the correct answer.
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Explanation:
An economical trapezoidal channel section is one in which the cross-sectional area of the channel is minimized for a given flow rate. The hydraulic mean radius (R) is an important parameter that determines the hydraulic efficiency of a channel. It is defined as the ratio of the cross-sectional area of the flow to the wetted perimeter.
R = A/P
where A is the cross-sectional area and P is the wetted perimeter.
For an economical trapezoidal channel section, the hydraulic mean radius equals half the depth of flow. This is because a trapezoidal channel with this proportion has the minimum wetted perimeter for a given cross-sectional area, which results in a lower energy loss due to friction.
Therefore, option B is the correct answer.