A uniform disk turns at 2.4 rev/s around a frictionless spindle. A non-rotating rod, of the same

Question:

A uniform disk turns at 2.4 rev/s around a frictionless spindle. A non-rotating rod, of the same mass as the disk and length equal to the disk€™s diameter is dropped onto the freely spinning disk, Fig. 8-49. They then both turn around the spindle with their centers superposed. What is the angular frequency in rev/s of the combination?

A uniform disk turns at 2.4 rev/s around a frictionless