1. The problem statement, all variables and given/known data What is the angular inertia of a disk (cylinder) with... Maximal radius, rmax = 10cm Thickness, h = 4cm density, d = 3g/cm3 rotational axis in its centre (like the axis of clock hand in a disk shaped clock) Please show and explain your procedure in finding the answer. 2. Relevant equations Angular inertia of point mass = (radius from rotational axis)2 × mass of point mass 3. The attempt at a solution I see that this question obviously involve calculus, but I don't have any real understanding of calculus. I think we need to consider the cylinder as composed of infinitely many concentric tubes each with a negligible volume (the distance between the tubes' inner and outer radius is assumed to be zero) and then add the individual angular inertia of all of the tubes. I apologize for any spelling/grammar mistake and any misuse of terminology, please explain any calculus stuff that you would use.