A uniform disk of mass m and radius r is attached at its edge to a flexible pivot on the ceiling. It is given a small displacement perpendicular to the plane of the disk, so that it begins to oscillate perpendicular to the plane of the disk. What is the period of oscillation? The moment of inertia of a disk about the axis going through its center and perpendicular to the plane it’s in is I_{\text {disk }}=\frac{1}{2} m r^{2}
Answer Choices
A. \pi \sqrt{2 r / 5 g}
B. \pi \sqrt{5 r / g}
C. \pi \sqrt{6 r / g}
D. 2 \pi \sqrt{r / g}
E. 2 \pi \sqrt{2 r / g}
