Question

The Froude number of flow in a rectangular channel is 0.8. If the depth of flow is 2.5 m, the critical depth is ___

• A. \( 10^3 \) m
• B. \( 10^0 \) m
• C. \( 10^2 \) m
• D. \( 10^{3} \) m

Hint:

For open channel flow, Froude number plays an important role in determining the flow type (subcritical, critical, or supercritical).

Answer 1

The Correct Option is D

The Froude number \( Fr \) is related to the depth of flow \( h \) and the critical depth \( h_c \) by the equation: \[ Fr = \frac{V}{\sqrt{g h}} \] where \( V \) is the velocity of the flow and \( g \) is the acceleration due to gravity. For \( Fr = 0.8 \), the critical depth can be calculated as \( 10^3 \) meters.