[填空题]
A uniform disk turns at 2w 66ssh 9p55obp.vx eqba.pu,oi1x k8.4aw-5v(yb 6kh3 cbhh l lq mqql12:1;it $rev/s$ 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? $rev/s$