On a horizontal, frictionless surface, a cube of edge $d=10~ cm
$ vand of uniform mass distribution, is sliding at a velocity of $v_0$. At some point the cube reaches a slope of an angle of inclination of $\alpha=30^\circ$. The «fault line» between the slope and the ground is perpendicular to the direction of travel of the cube. The front edge of the cube which is in contact with the ground gets stuck at the fault line totally inelastically, so that the cube topples.