Fig. 2. (Color online) elastic collision in case the cue ball is heavier and bigger than the target ball. (a) Before collision. (b) At the moment of contact, the target ball scatters with velocity u2→, again into the direction of the line that connects the two centers of the balls. (c) The triangle constituted by the three velocity vectors u1→, αu2→ and v→.
© NPSM
