VOID ratio (E):Void ratio is usually defined as the ratio of the volume of VOIDS to the total volume of SOIL solid.POROSITY (n):Porosity is defined as the ratio of the volume of voids to the total volume of the soil.The relationship between void ratio and porosity are as follows:\(\rm{e=\frac{n}{1-n}\; and\; n=\frac{e}{1+e}}\)