The GATE Grind

GATE 2025 CE (CE2) – Question 16

Hydraulics · Channel hydraulics: specific energy, critical flow, uniform flow, hydraulic jump · 1 mark · Multiple choice

A hydraulic jump occurs in an open channel when the slope of the channel changes from ______.

  1. MILD slope to STEEP slope
  2. STEEP slope to MILD slope
  3. MILD slope to ZERO slope
  4. STEEP slope to a STEEPER slope

Practise this question in The GATE Grind →

Show answer and explanation

Correct answer: (B) STEEP slope to MILD slope

Explanation

A hydraulic jump is the change from supercritical to subcritical flow. On a steep slope the flow is supercritical and on a mild slope it is subcritical, so a jump forms where a steep slope changes to a mild slope. A change from mild to steep gives a drop (a hydraulic fall).