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
What are the advantages of using a glass substrate for a magnetic disk?
Introduction
Magnetic disk drives are the most common way to transfer data between computers and other electronic devices. They use a magnetic medium, like a hard drive or tape, to store information. The key advantage of using glass as the substrate for a magnetic disk is that it has excellent temperature stability when compared with other materials such as aluminum or steel.
Soft magnetic materials
Soft magnetic materials are good for magnetic disks. They are not as hard as hard magnetic materials, and they can be used in the same way as hard magnetic materials. Soft magnetic materials are more expensive than hard ones, but they have many advantages over these other types of media.
Reduced friction
A glass substrate is a good choice for magnetic disks because it has a low coefficient of friction. In other words, the material has very high lubricating properties and reduces friction between the two surfaces. This means that your disk will be able to spin smoothly without wearing out over time or gradually slowing down due to excessive wear on either side of its surface area (which would cause it to skip).
Glass is also less likely than other materials like plastic or steel to scratch when spun in one direction too long; this makes it easier for people who work with disks every day (like teachers) because they don’t have to worry about damaging their equipment!
High coercivity
The coercivity of a material is the measure of how strongly it can be magnetized. It’s defined as:
Coercivity = Oe (Oersted)
The higher your coercivity, the better. A higher number means you’ll have less difficulty reading and writing information on your diskette or disk drive.
Excellent temperature stability
Glass is an excellent substrate for magnetic disks because of its excellent thermal and electrical properties. It can be used as a substrate in the manufacture of both hard disk drives and floppy diskettes.
Glass has good insulating properties, which makes it suitable for use in heat sinks or other device cooling applications. It also exhibits low thermal conductivity (0.03W/mK at room temperature), which means that it has little tendency to conduct heat away from your system very quickly when it’s being used as a storage medium.
Energy saving
The glass substrate is very smooth and easy to work with. It also has a high tensile strength, which means that it can withstand great pressure without breaking or crushing. The glass substrate is also extremely flexible, so that you can bend it into any shape you want without having to worry about damaging the disk. This makes it ideal for making magnetic disks because they need to be curved in order to fit on top of each other without overlapping or being too close together.
Glass has been used as a substrate for magnetic disks since ancient times: Ancient Greeks used glass beads embedded into clay tablets containing information about mathematical calculations; Romans used them as mirrors for their armies’ helmets; Egyptians made wine glasses out of molten sandblasted quartz crystals (which had been imported from North Africa); ancient Chinese used porcelain enamels painted onto lead crystal plates before setting them into dioramas depicting scenes from their history books (which were later destroyed).
Glass is a very good substrate for magnetic disks, but it needs to be heated to the appropriate temperature before using it.
Glass is a very good substrate for magnetic disks, but it needs to be heated to the appropriate temperature before using it. Glass is a soft material, so it can be used in a wide range of applications.
Glass can also be used as a protective layer on top of other materials such as plastic or metal.
Conclusion
In conclusion, we can say that glass is a very good substrate for magnetic disks. In addition, it needs to be heated to an appropriate temperature before using it. If you have any questions, please contact us and we will be happy to assist you.