In the theory of the propagation of light through clouds, developed by Mecke, Albrecht, and Gordov, the properties of the medium are represented by two coefficients which express the disposition of the element of a cloud, that is, a drop of water, to diffuse and absorb light, respectively. In the present work, it is demonstrated how the absorption coefficient can be expressed as a function of the physical characteristics of the water drop, determining theoretically for light however diffused and polarized which penetrates this water drop, the quantity which will be absorbed and dissipated.