27.5.2. Philip’s Equation

Try these first

1. 1.

   What does S represent in Philip's Equation?

   Hint

   Remember, it starts with an 'S' for 'Soil absorption'.

2. 2.

   What is used to represent the steady-state infiltration rate in Philip's Equation?

   Hint

   A stands for 'Always constant' after a while.

3. 3.

   What does Philip's Equation predict?

   • Infiltration rate based on time
   • Soil type classification
   • Rainfall intensity analysis

   Hint

   Think about the relationship between rain and absorption.

4. 4.

   Philip's Equation involves which of the following components?

   • True
   • False

   Hint

   Recall the variables defined in the equation.

5. 5.

   A soil has a sorptivity (S) of 0.1 m/day and a steady-state infiltration rate (A) of 0.2 m/day. Calculate the infiltration rate after 9 days.

   Hint

   Focus on the square root of time and multiply it properly.

6. 6.

   Discuss how changes in soil texture (e.g., from clay to sandy) affect the components of Philip's Equation and resulting infiltration rates.

   Hint

   Think about how the water moves differently through various soil types.