Hi, I'm practicing for the physics olympiad qualifier and I came across this problem: A spaceborne energy storage device consists of two equal masses connected by a tether and rotating about their center of mass. Additional energy is stored by reeling in the tether; no external forces are applied. Initially the device has kinetic energy E and rotates at angular velocity wEnergy is added until the device rotates at angular velocity 2w What is the new kinetic energy of the device? I know that E=.5Iw^2, but why does Ioda decrease by a factor of two? Thanks.