1. The problem statement, all variables and given/known data A gyroscope consists of a uniform disc of mass M and diameter d attached at its centre to a light spindle of length l perpendicular to the plane of the disc. i) Show that the moment of inertia, I, of the disc around the axis of the spindle is Md²/8. 2. Relevant equations I=MR² Moment of inertia 3. The attempt at a solution I cant understand why it becomes I=Md²/8 as R=d/2 and R²=d²/4 not d²/8 or am i missing something?