Question

Hydraulic jump is

• A. Uniform flow
• B. Gradually varied flow
• C. Rapidly varied flow
• D. Critical flow

Hint:

Flow classifications: \[ \boxed{ \begin{aligned} \text{Uniform Flow} &\rightarrow \text{Depth constant}\\ \text{Gradually Varied Flow} &\rightarrow \text{Depth changes slowly}\\ \text{Rapidly Varied Flow} &\rightarrow \text{Hydraulic Jump} \end{aligned} } \]

Answer 1

The Correct Option is C

Step 1: List the categories of open channel flow.
Flow in channels is grouped as uniform flow, gradually varied flow (GVF) where depth changes slowly over a long distance, and rapidly varied flow (RVF) where depth changes sharply over a short length.
Step 2: Look at what happens in a hydraulic jump.
During a jump, the flow depth jumps from a shallow, fast (supercritical) depth to a deeper, slow (subcritical) depth within just a few channel widths, along with turbulence and energy loss.
Step 3: Match this behaviour to a category.
Such an abrupt change over a short length is the defining feature of rapidly varied flow.
\[ \boxed{\text{Rapidly Varied Flow}} \]