Where formula _ 2 is the time for a liquid of formula _ 6 viscosity formula _ 3 and surface tension formula _ 4 to penetrate a distance formula _ 5 into the capillary whose pore diameter is dynamic .
Where formula _ 2 is the time for a liquid of dynamic viscosity formula _ 3 and surface tension formula _ 4 to penetrate a distance formula _ 5 into the capillary whose pore diameter is formula _ 6 .