1. A skater extends her arms, holding a 2kg mass in each hand. She is rotating about a vertical axis at given rate. She brings her arms inward toward her body in such a way that the distance of each mass from the axis changes from 1m to 0.50 m. what is her new rate of rotation.
2. A mass m is attached to a massless spring with a force constant k. The mass rests on a horizontal frictionless surface, The system is compressed distance x from the spring's initial position and then released. Find an expression for the momentum of the mass when the spring passes its equilibrium point.