An experimental study of a lyotropic nematic liquid crystal (CsPFO in a water solution) confined to a cylindrical tube is presented. The structure of the sample is controlled by a magnetic field. A small ac voltage is applied along the tube for conductivity measurements. Elastic constants and conductivity constants of the material an determined from static measurements at different magnetic fields. The method is also used to determine the rotational viscosity gamma(1) from dynamic response under sudden changes of the : magnetic field. The dynamic measurements are analyzed in the framework of the Leslie-Ericksen theory. It is shown that although the dynamic behavior can be qualitatively explained with a single effective rotational viscosity gamma(1), back flow effects have to be taken into account should the analysis yield consistent values for gamma(1). The results obtained by this method agree well with other experimental studies.