3.2. Hydraulic Radius Calculation

Try these first

1. 1.

   Define hydraulic radius and provide its formula.

   Hint

   Think about how area and perimeter relate in a flow context.

2. 2.

   What is the formula for wetted perimeter in a trapezoidal channel?

   Hint

   Consider how trapezoidal geometry can be used in calculations.

3. 3.

   What is the formula for hydraulic radius?

   • A/P
   • P/A
   • A+P

   Hint

   Remember the relationship between area and perimeter.

4. 4.

   True or False: Manning's equation can be applied to circular channels.

   • True
   • False

   Hint

   Consider how Manning's equation was derived.

5. 5.

   A trapezoidal channel has a bottom width of 5m and a depth of 2m with side slopes of 1:2. Calculate the hydraulic radius and assess its impact on flow efficiency.

   Hint

   Focus on deriving each dimension step by step.

6. 6.

   For a circular channel of 1m in diameter carrying water at a depth of 0.5m, compute hydraulic radius and determine the discharge using Manning's equation, considering n=0.015.

   Hint

   Use trigonometric functions correctly to derive angles.