In the arrangement shown in Fig. 1.56 the mass of the uniform solid cylinder of radius \(R\) is equal to \(m\) and the masses of two bodies are equal to \(m_{1}\) and \(m_{2} .\) The thread slipping and the friction in the axle of the cylinder are supposed to be absent. Find the angular acceleration of the cylinder and the ratio of tensions \(T_{1} / T_{2}\) of the vertical sections of the thread in the process of motion.