[填空题]
A uniform disk turnsn(+,19i ckut2yv nnif aoc trvpo80 +ek4yv5 1vt 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? $rev/s$