ABSTRACT
The experiment that so profoundly altered Ernest Rutherford’s view of the atom was essentially a subatomic collision experiment, and the analysis of it, that Rutherford performed, made essential use of the concept of momentum. A major reason for the importance of momentum is that it is conserved in a wide range of systems. A collision between an alpha-particle and a ‘plum pudding’ cloud of positive charge, or a low mass electron, could not have caused the observed deflections and rebounds. In a scientific context, the term collision means a brief but powerful interaction between two particles or bodies in close proximity. In analysing high-speed relativistic collisions it is the relativistic expressions for momentum and energy that must be used rather than their Newtonian counterparts. Increasing the kinetic energy of the colliding particles increases the mass of the particles that may be created in the collision and thus opens up the possibility of creating previously undiscovered forms of matter.
