Two point masses, each of mass 5 kilogram are joined by a light straight rod of length 1 meter. This "dumbbell" is located on a horizontal frictionless surface, and set into rotation, about a vertical axis through the center of mass, with an angular speed of 4 rad/s. Suddenly, the rod twice in length.
1. Find the initial moment of inertia of the system?
2. Find the initial angular momentum of the system?
3. Find the initial kinetic energy of the system?
4. Find the final angular velocity of the system?
5. Find the final kinetic energy of the system?