Simulation snapshots of the total force (colour scale) during the single eruption in the slow-wind (top panel) and faster-wind case (bottom panel). The white and red lines represent selected magnetic field lines. The vectors indicate the following forces: T_B (red), −∇P_B (blue), and −∇P_P (black). The snapshots were taken at 14 h (top) and 12 h (bottom) from the start of shearing, such that the front of both CMEs is at ≈2 R_⊙.