Two disks are mounted (like a merry-go-round) on low-friction bearings on the same axle and can…

Two disks are mounted (like a merry-go-round) on low-friction bearings on the same axle and can be brought together so that they couple and rotate as one unit. The first disk, with rotational inertia 3.00 kg m about its central axis, is set spinning counterclockwise at 550 rev/min. The second disk, with rotational inertia 6.40 kg m about its central axis, is set spinning counterclockwise at 800 rev/min. They then couple together. (a) What is their angular speed after coupling? rev/min (b) If instead the second disk is set spinning clockwise at 800 rev/min, what is their angular speed after they couple together? rev/min