# Secondary Storage

 Question 1
A magnetic disk has 100 cylinders, each with 10 tracks of 10 sectors. If each sector contains 128 bytes, what is the maximum capacity of the disk in kilobytes?
 A 12,80,000 B 1280 C 1250 D 1,28,000
ISRO CSE 2020   Computer Organization
Question 1 Explanation:
 Question 2
A particular disk unit uses a bit string to record the occupancy or vacancy of its tracks, with 0 denoting vacant and 1 for occupied. A 32-bit segment of this string has hexadecimal value D4FE2003. The percentage of occupied tracks for the corresponding part of the disk, to the nearest percentage is:
 A 12 B 25 C 38 D 44
ISRO CSE 2018   Computer Organization
Question 2 Explanation:
 Question 3
SATA is the abbreviation of
ISRO CSE 2017   Computer Organization
Question 3 Explanation:
 Question 4
Consider a disk pack with 16 surfaces, 128 tracks per surface and 256 sectors per track. 512 bytes of data are stored in a bit serial manner in a sector. The capacity of the disk pack and the number of bits required to specify a particular sector in the disk are respectively:
 A 256 Mbyte, 19 bits B 256 Mbyte, 28 bits C 512 Mbyte, 20 bits D 64 Gbyte, 28 bits
ISRO CSE 2016   Computer Organization
Question 4 Explanation:
 Question 5
A hard disk system has the following parameters :
Number of tracks =500
Number of sectors/track =100
Number of bytes /sector =500
Time taken by the head to move from one track to adjacent track =1 ms
Rotation speed =600 rpm.
What is the average time taken for transferring 250 bytes from the disk ?
 A 300.5 ms B 255.5 ms C 255 ms D 300 ms
ISRO CSE 2015   Computer Organization
Question 5 Explanation:
 Question 6
Six files F1, F2, F3, F4, F5 and F6 have 100, 200, 50, 80, 120, 150 records respectively. In what order should they be stored so as to optimize act. Assume each file is accessed with the same frequency
 A F3, F4, F1, F5, F6, F2 B F2, F6, F5, F1, F4, F3 C F1, F2, F3, F4, F5, F6 D Ordering is immaterial as all files are accessed with the same frequency.
ISRO CSE 2015   Computer Organization
Question 6 Explanation:
 Question 7
Consider a typical disk that rotates at 15000 rotations per minute (RPM) and has a transfer rate of 50x$10^{6}$ bytes/sec. If the average seek time of the disk is twice the average rotational delay and the controller's transfer time is 10 times the disk transfer time, the average time (in milliseconds) to read or write a 512-byte sector of the disk is ______.
 A 8.2 B 6.1 C 3.5 D 9.5
GATE CSE 2015 SET-2   Computer Organization
Question 7 Explanation:
 Question 8
Consider a disk pack with a seek time of 4 milliseconds and rotational speed of 10000 rotations per minute (RPM). It has 600 sectors per track and each sector can store 512 bytes of data. Consider a file stored in the disk. The file contains 2000 sectors. Assume that every sector access necessitates a seek, and the average rotational latency for accessing each sector is half of the time for one complete rotation. The total time (in milliseconds) needed to read the entire file is ____________.
 A 12530 B 14020 C 17564 D 15642
GATE CSE 2015 SET-1   Computer Organization
Question 8 Explanation:
 Question 9
In case of a DVD, the speed of data transfer is mentioned in multiples of?
 A 150 KB/s B 1.38 MB/s C 300 KB/s D 2.40 MB/s
ISRO CSE 2013   Computer Organization
Question 9 Explanation:
 Question 10
Consider a hard disk with 16 recording surfaces (0-15) having 16384 cylinders (0-16383) and each cylinder contains 64 sectors (0-63). Data storage capacity in each sector is 512 bytes. Data are organized cylinder-wise and the addressing format is (cylinder no., surface no., sector no.). A file of size 42797 KB is stored in the disk and the starting disk location of the file is (1200, 9, 40). What is the cylinder number of the last sector of the file, if it is stored in a contiguous manner?
 A 1281 B 1282 C 1283 D 1284
GATE CSE 2013   Computer Organization
Question 10 Explanation:
There are 10 questions to complete.