In many undergraduate physics courses, mechanics is
taught early in the syllabus because much of it, in particular,
linear kinematics, is a review of what is taught in pre-university
courses. However, conceptualizing and understanding
the moment of inertia often prove to be difficult for
students, even for simple symmetric systems. Rimoldini and
Singh found that many students had difficulties with concepts
in rotational and rolling motion, such as rotational
energy and moment of inertia.