This article presents a conceptual analysis on the relationship between the sharpness parameter m, of the Rosin-Rammler distribution, and the parameter alpha, its correspondent in the Whiten logistic distribution function. The solids split curve is approximated by a Rosin-Rammler distribution function in the Plitt model for hydrocyclone, while, alternatively, the logistic distribution function is adopted for the partition in the Lynch-Rao model. The results show that the two parameters can be related to the following equation, achieved by nonlinear regression analysis: alpha = 34,555 x exp [-3,9/ m0,5984]
probability; Rosin-Rammler distribution; Whiten distribution; hydrocyclones