In the apparatus below a 50g mass is hung from the pulley and released. A disk is placed on the platform. The platform has a radius of 5cm.
The disk and the platform go from rest to an angular velocity of 8.5 rad/s in 2.5 seconds. What is the moment of inertia of the disk? What is its mass? Ignore the mass of the platform. Show your work and explain your reasoning.
How would your answer change if instead of a disk, the experiment was done using a ring with the same mass as the disk. Show your work and explain your reasoning.