Topic: Fluid Mechanics
Which is the most economical depth of flow in an open rectangular channel?
- A. Depth of flow equals to the width of channel
- B. Depth of flow is double the width of channel
- C. Depth of flow is half of the width of channel
- D. Depth of flow is 1/3rd the width of channel
Answer: C. Depth of flow is half of the width of channel
Explanation: For a rectangular channel to be most economical (i.e., yielding maximum discharge for a given cross-sectional area), the hydraulic radius must be half the depth, which translates to the depth of flow being exactly half the width of the channel.