Abstract:
A discussion of the kinematics of the relative rotational motion is presented. The central role of the correct understanding of the change of a vector is emphasized. The relation between the first and second derivatives of a vector in two reference systems is deduced. These relations are applied to a system fixed to the Earth surface. The hierarchy of approximations involved in this example is presented and the method of succesive approximations (perturbation theory) is introduced in this context.