The water depth in a channel corresponding to minimum specific energy is designated as ________________?
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Answer: B. Critical depth
Explanation
Critical depth corresponds precisely to the flow condition that yields minimum specific energy. At this threshold, specific energy reaches its lowest possible value for a constant discharge rate. Fluid mechanics principles establish this fundamental relationship for open channel hydraulic systems. Specific energy is the sum of pressure head, velocity head, and elevation above the channel bed. Plotting specific energy against flow depth reveals a characteristic curve with a clear minimum point. The Froude number equals one when flow occurs at this critical minimum energy state.
Hydraulic structures like broad crested weirs utilize critical depth to measure open channel discharge. Engineers design canal transitions to navigate through critical depth without causing undesirable standing waves. Understanding minimum specific energy prevents flooding and structural instability in conveyance channels. Option A refers to normal depth where gravitational forces balance frictional resistance in uniform flow. Option C denotes full supply depth used in canal operational design rather than energy minimization. Option D is incorrect because the critical depth answer is explicitly listed among the choices.
- Subject
- Agriculture
- Category
- Agriculture
- Topic
- —
- Difficulty
- medium
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