  The concepts of relative velocity and acceleration, deviation velocity and
acceleration and relative momentum of point particles in spaces (manifolds),
the tangent bundle of which is equipped with a transport along paths, are
introduced. If the tangent bundle is endowed also with a metric, it gives rise
also to the notion of a relative energy. Certain ties between these quantities
are considered. The cases of massless particles and of special relativity are
presented in this context.
