The figure shows an overhead view of a ring that can rotate about its center like a merry-go-round. Its outer radius R2 is 0.9 m , its inner radius R1 is R2 /2, its mass M is 7.4 kg , and the mass of the crossbars at its center is negligible. It initially rotates at an angular speed of 8.9 rad/s with a cat of mass m = M/4 on its outer edge, at radius R2. By how much does the cat increase the kinetic energy of the cat-ring system if the cat crawls to the inner edge, at radius R1? Number Units
