Question

The sequent depth ratio of a hydraulic jump in a rectangular channel is 16.48. What is the Froude number (approximate) at the beginning of the jump?

• A. 5.0
• B. 9.0
• C. 8.0
• D. 12.0

Answer 1

The correct option is D 12.0

The sequent depth ratio for a rectangular channel is given by

$\frac{y_2}{y_1}=\frac{1}{2}(-1+\sqrt{1+8F_1^2})$

$\Rightarrow 16.48=\frac{1}{2}(-1+\sqrt{1+8F_1^2})$

$\Rightarrow 1+8F_1^2=1153.28$

$\Rightarrow F_1=\sqrt{144}$

$\Rightarrow F_1=12.0$