Answer:
Porosity is the phenomenon or tendency of the capacity of a ground surface to hold water under the ground in the space called a pore. Permeability and impermeability are depended on the shape of pores and how they are connected with one another.
The size of pores and how they are interconnected decide the flow of the water from one pore to the neighboring pores. For better understanding imagine the size of the pores is larger so there will be less friction or hurdles in the flowing of water from the sides of the pores. Larger and well-connected pores increase the permeability whereas in impermeable ground surface the size of the pores is small and ill-connected that increases friction.
