rotational

The ortho molecules rotate with odd rotational quantum numbers, while the para molecules rotate with even quantum numbers.

The total, however, of the rotational moment of momentum of the system barely reaches two per cent.

How can one who is ignorant of the existence and characteristics of rotational inertia understand a galvanometer?

By this time the student should have found himself sufficiently prepared to take up problems of rotational motion.

Searching problems and discussion are instigated at once, and the notion of rotational equilibrium and force moments brought in.