... for the right sector. When the arm moves to a track, it must wait for the right sector to appear under the head. That takes time also. On the average, the platter must rotate ½ revolution, to reach ... The closer to the center of the disk the faster the rotation speed.In the music CD, data are read sequentially. Therefore, rotation speed variation is not necessary The CD-ROM disk on the other ... music storage media. The CD-ROM The CD-ROM (Read Only Memory) came as an extension of the CD in 1984. In principle, the media and the drives are the same. The difference is in the data storage...