Q125
The upper surface of a weir over which water flows is known is
A.
crest
AnswerB.
nappe
C.
sill
D.
weir top
Answer: Option A
Solution
Answer: Option A
Solution:
The upper surface of a weir over which water flows is called the crest.The crest is the highest point of the weir, and it controls the flow of water over the structure.
The nappe refers to the sheet of water that flows over the weir crest.
The sill is the bottom edge or base of the weir structure, which supports the crest.
Weir top is not a technical term used in hydraulics and fluid mechanics.
Thus, the correct answer is crest.