Say car A is stationary, and in front, car B is also stationary. Car B then, at a slow speed, begins to reverse, and hits car A, causing damage to the front-end of car A. There is no damage to the rear bumper of car B. Using momentun transfer, energy transfer?, or what have you, is there any way of proving that car B reversed into car A, while disproving car A rear-ending car B? Thanks for you thoughts.