Phenomenon of force impulse restitution in collision modelling

The rightness of the Newtonian hypothesis concerning a constat value of the coefficient of restitution $ R$ has been confirmed in the paper with reference to collisions in which the loss of energy occurs in conseqence of material damping. For collisions of different nature, when $ R$ depends on the density of the energy flux $ {\Phi}$, the paper points to the possibility of extending this notion to the case of eccentric collision. The possibility of describing $ R$ as a random function of $ {\Phi}$ has been shown as well.