In most literature on lubrication theory, the assumption of   is considered to solve the Navier-Stokes equations in which inertial forces are neglected in comparison with the viscous ones. In problems of bearing with high speed motion, neglecting the inertial forces can not be utilized. In this study, the Navier-Stokes equations for a slider bearing are solved, considering both the inertial and the viscous forces. Then, the effective forces were computed and analyzed. Finally, the results were compared with the available approximate ones, which showed close agreements.