[填空题]
A uniform disk turnsu 3pblzd7/xrjg-r2sikj,r k149 k;la s1h9nb txy px4cl +5d8 at 2.4 $rev/s$ around a frictionless spindle. A nonrotating 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? $rev/s$