What is the number of disk cylinders in a disk? [closed]

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A disk has the following characteristics :

• bytes per sector = 512

• sectors per track = 50

• tracks per surface = 2000

• number of platters = 5

• average rotational speed =5400 rpm

• average seek time = 10 ms

What is the number of disk cylinders ?

Isn't it one whole cylinder like the following screenshot seems to show or is cylinder a synonym of platter ?

Answer 1

From this Wiki post - highlighting mine:

Cylinders

A cylinder is a division of data in a disk drive, as used in the CHS addressing mode of a Fixed Block Architecture disk or the cylinder–head–record (CCHHR) addressing mode of a CKD disk.

The concept is concentric, hollow, cylindrical slices through the physical disks (platters), collecting the respective circular tracks aligned through the stack of platters. The number of cylinders of a disk drive exactly equals the number of tracks on a single surface in the drive. It comprises the same track number on each platter, spanning all such tracks across each platter surface that is able to store data (without regard to whether or not the track is "bad"). Cylinders are vertically formed by tracks. In other words, track 12 on platter 0 plus track 12 on platter 1 etc. is cylinder 12.

Conceptually, a cylinder is "standing on top of one track and looking straight down through all of the platters." If you have 2000 tracks, you have 2000 cylinders.