This work involves the determination of the critical size which we can define as the largest partide which can float, and the critical density, which is the densest partide which can float at specific radius and contact angle, it also indudes calculation of height maxima and masimum force aeting on the partide under the same conditions. The calculations require not only the limit of possible equilibrium confiqurations but also the stability of the partide. Also the critical densities maximum force aeting on sphere, and maximum heights, along with the other forces aeting on the partide were calculated for various contact angles and as reduced value of R equals to 0.5. There is a linear relationship between contact angle and critical density.