Heuristic judgment of mass ratio in two-body collisions. Perception and Psychophysics
Gilden, D. L., & Proffitt, D. R.

The logic of judging relative mass from a two-body collision is developed from data presented by Runeson and Vedeler (1993). We analyze data from two experiments on a point-by-point basis and show that there is strong support for the theory that mass ratio judgments are mediated by separate speed and angle heuristics. This analysis is accomplished by reducing the collision event to two elementary features; the presence of ricochet and the ratio of exit speeds. The heuristics that both ricochet and greater exit speed specify relative lightness are shown to explain the basic patterns of data presented by Runeson and Vedeler.