Phoenix Business Daily

What is the moment of inertia for this problem?

A circular disk rotating at 800rpm is brought into contact with a stationary disk whose moment of inertia is 3 times the rotating disk's moment of inertia. What is the speed of the combination?

Public Comments

1. 200 rpm The moment of inertia of the two disks together is four times the moment of inertia of the initially rotating disk. The speed of the combination is one-fourth the initial angular speed.