Comparison between the disk force in the three different cases, F^BT, F^W, and F^SR under the assumption that R_in = 0 in the computation of F^W, and F^SR. The disk-density profile has a p = 1 coefficient. The filled circles are the force values computed numerically with the code FARGO. The enclosed figure shows a more detailed view of the force values near the radial center of the disk. F^BT, F^W, and F^SR are indistinguishable, confirming their equivalence. However, all the analytical estimates do not properly match the numerical solutions close to the star.