The object of this thesis was to investigate the slip-velocity ratio between the phases in the two-phase flow of saturated water. Because the usual flow measurements of pressure, temperature, and flow are not sufficient to adequately determine this ratio, a test configuration was designed to also measure the thrust of the expanding flow. This necessitated the establishment of a test configuration and a procedure that could be used to measure small values of thrust. This vale was needed in order to solve the simultaneous equations for momentum, energy, and quality, of the liquid-vapor stream. The results show the respective velocities at which the vapor and liquid phases are traveling. The solution is based on the flow being one-dimensional and in thermodynamic equilibrium. It was also assumed that the vapor phase and liquid phase were separated.