Distance-time and weight-time imbibition measurements with liquids having different densities, surface tensions, and viscosities have been carried out on silica gel plates in order to determine contact angles, by employing the parabolic form of the Washburn equation and the physical model that considers the difference in pressure at the liquid-vapor interface in terms of the Laplace equation. A comparison of the contact angles obtained by these two experimental techniques showed that the results are the same if the effective porosity of the porous solid determined independently by each capillary penetration experiment is utilized to analyze the weight-time experimental data.