1. SCIENCE 8 TOPIC 9

2. The three things that can happen when precipitation falls to earth

3. The three things that can happen when precipitation falls to earth
Runs off

4. The three things that can happen when precipitation falls to earth
Runs off
Evaporate

5. The three things that can happen when precipitation falls to earth
Runs off
Evaporate
Infiltrate

6. The definition to porosity

7. The definition to porosity
Percentage of open space in a material

8. What determines porosity?

9. What determines porosity?
NOT particle size because our lab results proved that

10. What determines porosity?
Particle shapes – round or square

11. What determines porosity?
Particle shapes – round or square
Particle packing

12. What determines porosity?
Particle shapes – round or square
Particle packing
Particle size mixing – small or large

13. Permeability defined

14. The rate that water can flow through a sample of soil
Permeability defined
The rate that water can flow through a sample of soil

15. Factors that determine permeability

16. Factors that determine permeability
#1: The size of the pores. The larger the pores the greater the permeability

17. Factors that determine permeability
#2: The inter-connection of the pores spaces. Greater inter-connection means a more direct pathway for the water to pass through the soil.

18. Permeability and pore size relationship

19. Permeability and pore size relationship
Direct: Greater pore size means greater permeability

20. Three conditions under which run-off will occur

21. Three conditions under which run-off will occur
Three conditions under which run-off will occur. The first is if the soil is saturated with water.

22. Three conditions under which run-off will occur
Three conditions under which run-off will occur. The second is if the rate of rainfall is greater than the rate of soil infiltration.

23. Three conditions under which run-off will occur
Three conditions under which run-off will occur. The third is if the slope is too steep for the water to infiltrate into the ground.

24. How does water move upward in a soil?

25. How does water move upward in a soil?

26. Two factors contribute to capillary action: the first is cohesion is where water molecules grab onto each other

27. Two factors contribute to capillary action: The second is adhesion is where water molecules grab onto other surfaces and try to pull themselves upward

28. So, can you explain how soil moves upward in a soil by capillary action?

29. What is the relationship between capillary action and particle size?

30. What is the relationship between capillary action and particle size?
Indirect…the greater the particles size the less capillary action.

31. What is the relationship between capillary action and particle size?
Indirect…the greater the particles size the less capillary action.
Why?

32. What is the relationship between capillary action and particle size?
Because the greater particle sizes do not fit very well together leaving very large pore spaces. Capillary action works best with very small pore spaces

33. The two types of wells
Gravity well

34. The two types of wells
ARTESIAN
WELL