**Question 1(10 Points)**

**What are the advantages of using a glass substrate for a magnetic disk? **

**Question 2 (10 Points)**

**Explain serpentine recording. **

**3.Explain the difference between a simple CAV system and a multiple zone recording system. **

**4.What differences between a CD and a DVD account for the larger capacity of the **

**DVD? **

**5.Consider a single-platter disk with the following parameters:**

**Rotation speed:**7200 rpm;**Number of tracks on one side of platter:**30,000**Number of sectors per track**: 600;**Seek time:**one ms for every hundred tracks traversed.**Assumption:**Let the disk receive a request to access a random sector on a random track and assume the disk head starts at track 0.

** What is the average seek time? **

*********Explain your reasoning and show your mathematical calculations on how you derived your answer **

**6.****Consider a single-platter disk with the following parameters:**

**Rotation speed:**7200 rpm;**Number of tracks on one side of platter:**30,000**Number of sectors per track**: 600;**Seek time:**one ms for every hundred tracks traversed.**Assumption:**Let the disk receive a request to access a random sector on a random track and assume the disk head starts at track 0.

**What is the average rotational latency?**

*********Explain your reasoning and show your mathematical calculations on how you derived your answer **

**7.****Consider a single-platter disk with the following parameters:**

**Rotation speed:**7200 rpm;**Number of tracks on one side of platter:**30,000**Number of sectors per track**: 600;**Seek time:**one ms for every hundred tracks traversed.**Assumption:**Let the disk receive a request to access a random sector on a random track and assume the disk head starts at track 0.

**What is the transfer time for a sector?**

*********Explain your reasoning and show your mathematical calculations on how you derived your answer **

**8.****Consider a single-platter disk with the following parameters:**

**Rotation speed:**7200 rpm;**Number of tracks on one side of platter:**30,000**Number of sectors per track**: 600;**Seek time:**one ms for every hundred tracks traversed.**Assumption:**Let the disk receive a request to access a random sector on a random track and assume the disk head starts at track 0.

**What is the total average time to satisfy a request? **

*********Explain your reasoning and show your mathematical calculations on how you derived your answer **

**9.****Consider a magnetic disk drive with 8 surfaces, 512 tracks per surface, and 64 sectors per track. **

- Sector size = 1 kB.
- Average seek time = 8 ms,
- Track-to-track access time = 1.5 ms,
- Drive rotates at 3600 rpm.
**Successive tracks in a cylinder can be read without head movement.**

**What is the disk capacity?**

********Explain your reasoning and show your mathematical calculations on how you derived your answer **

**10.****Consider a magnetic disk drive with 8 surfaces, 512 tracks per surface, and 64 sectors per track. **

**Sector size = 1 kB.****Average seek time = 8 ms,****Track-to-track access time = 1.5 ms,****Drive rotates at 3600 rpm.****Successive tracks in a cylinder can be read without head movement.****What is the average access time?**********Explain your reasoning and show your mathematical calculations on how you derived your answer**

11. **Consider a magnetic disk drive with 8 surfaces, 512 tracks per surface, and 64 sectors per track. **

**Sector size = 1 kB.****Average seek time = 8 ms,****Track-to-track access time = 1.5 ms,****Drive rotates at 3600 rpm.****Successive tracks in a cylinder can be read without head movement.**

**Assume this file is stored in successive sectors & tracks of successive cylinders, starting at sector 0, track 0, of cylinder ****i****. **

**Estimate the time required to transfer a 5-MB file.**

********Explain your reasoning and show your mathematical calculations on how you derived your answer **

**12. ****Consider a magnetic disk drive with 8 surfaces, 512 tracks per surface, and 64 sectors per track. **

**Sector size = 1 kB.****Average seek time = 8 ms,****Track-to-track access time = 1.5 ms,****Drive rotates at 3600 rpm.****Successive tracks in a cylinder can be read without head movement.**

**What is the burst transfer rate? **

********Explain your reasoning and show your mathematical calculations on how you derived your answer **