The Physics of CDs and DVDs
Everywhere you look now days, you see or interact with CDs or DVDs; whether it is in the car, at work, or at home for pleasure, you deal with these modern marvels. Whatever the use, CD has become a reliable medium in which to distribute information, in a reliable way. The cost of a CD is very inexpensive, making it a popular choice by companies trying to advertise, or teach you about something. American On Line (AOL) is one example of companies who have chose this reliable source for communication. CD is the abbreviation for compact disk; DVD is the abbreviation for digital video disk or digital versatile disk. The difference between the two is the CD is audio, and the DVD is audio and visual. The objective of this paper is to help you to understand the physics surrounding the CD and DVD. The main focus of this paper is to inform the reader of all the things that take place when you watch a movie on a DVD player, starting with the CD itself. The laser reads the CD and converts it to the final product of what we see and hear.
Most CDs are made from polycarbonate plastic. This polycarbonate is a tough material that helps to prevent scratching. Scratching of a CD causes the laser, which reads the spiral data, to jump off track, allowing the CD to skip around and to distort whatever you are watching or listening to. According to How Things Work,
A CD is a fairly simple piece of plastic, about four one-hundredths (4/100) of an inch (1.2 mm) thick. Most of a CD consists of an injection-molded piece of clear polycarbonate plastic. During manufacturing, this plastic is impressed with microscopic bumps arranged as a single, continuous, extremely long spiral track of data. Once the clear piece of polycarbonate is formed, a thin, reflective aluminum layer is sputtered onto the disc, covering the bumps. Then a thin acrylic layer is sprayed over the aluminum to protect it. (Brian 1)
After that, you have a final product called a CD.
Often, you will hear about bumps on a CD. These bumps are what the laser reads. They are also sometimes referred to as pits. Bumps and pits are the same thing; it just depends on what side of the CD you are looking at.
12. DVDs are digital versatile disc, optical discs used to externally store data. DVDs have higher recording and retrieving speeds, are better suited for backing up information, and have higher capacity per device than
MP3 is a relatively new form of piracy, only being around for about ten years. The fact that the MP3 format takes up as little as one megabyte for a one minute clip, makes it an attractive storage factor for pirates. And with the CD-R and CD-RW drives, people can convert MP3 files to common CD format, burn to a CD, and play in any CD player, and be listening to a mix of their favorite songs within a half hour of downloading the song. With MP3 players becoming more and more popular options in cars, you can burn MP3 files directly to a CD without converting to a standard audio file and have over six hours of music on a single CD!
The DeCSS program was created by a group of three European programmers that called itself Masters of Reverse Engineering (MoRE). The media usually attributes its creation to a Norwegian teenager, Jon Johansen, although he has stated that he did not even do the crucial decryption portion [1]. DeCSS was created to provide a method of DVD playback under Linux, which at the time had no program capable of playing DVDs. In order to understand the basis for the case by the MPAA, it is necessary to first understand the encryption scheme employed by DVDs and how DeCSS circumvents this to facilitate playback.
Her novels reflect both the lack of hope that racism creates as well as the positivity that has encouraged the African American people to succeed despite the racist ideology that slowly tears them down. Morrison’s father showed “blatant hostility towards white people” through her younger years (Mobley 508). However her mother had a strong feeling that someday racism would come to an end in the United States, and race relations would improve. In her later years, Morrison moved to New York with her two children after being newly divorced and became an editor at Random House, where she worked with mostly black writers. Soon after moving to New York, she wrote her first novel The Bluest Eye in 1964 (508). In previous interviews Morrison states that she wrote the novel after a time of depression, but later revokes the statement by saying how the words she used don’t necessarily hold their true meaning. She says “they simply represent a different state. It’s an unbusy state, when I am more aware of myself than of others” (Smith
In “A Rose for Emily”, William Faulkner, the narrator creates this image of Emily to only benefit the townspeople and the town. The townspeople continue to torment Emily even when she has passed away. The town try’s to protect their image as a southern knit community, with her inheriting her father’s house, the town feels responsible for Emily at this point. Although they feel for Emily, they continuously
How a record player works is quite simple. A motor is somehow connected to a solid disc so that the disc is rotated at a constant speed. On top of the rotating disc (platter), The record is placed on top, with a slip mat in between. The slip mat can serve two functions. In the past to hold the record in place so that it would not rotate independently of the platter. Now, however, the slip mat serves a much different function. Instead of holding the record in place, the slip mat is now used to reduce the friction between the spinning platter and the record. This way a DJ can scratch (manually move the record, usually at high speeds) the record while the platter continues to spin underneath. Once the record is rotating, a stylus glides along the grooves and picks up the vibrations, these are then converted into audible sound.
Many of us are animal lovers, and I know that it hurts us to see any animal hurt, abused, or neglected. When you are ready to have your own dog and responsible enough to take care of it, make sure you are looking in the right places to find one. The pet store or an online ad is not the place to find your next best friend. By purchasing a pet from these places, you are fueling the pet mill industry, research laboratories and causing more animals to go through this everyday suffering. Shelters and rescue organizations are everywhere, and there are many animals that would love to be adopted and need your affection there. Think twice before buying your next puppy, you could save a life!
A value is a fundamental belief or practice about what is desirable, worthwhile, and important to an individual. My single most important value is family. I value my family because they are always there for me no matter what I do or say they will always love me. My next value is football. Football is my favorite sport by far and is the most fun to play and watch. I always no I will never be bored watching or playing football. I also value snowboarding. Whenever I am on the mountain snowboarding I forget about everything and just ride, it relieves my tension and makes me happy. I am going to college next year so my next value will be the school I will be attending: University of Minnesota Twin Cities Campus. Spending the ne...
Music piracy is the process of copying, or file sharing copyrighted materials illegally. Music theft hurts the artists that bring music to your ears due to the fact that they’re not receiving a decent amount of income because their songs are obviously getting stolen. A survey has identified that 70 percent of all 18 to 29 year olds have pirated music, TV shows, or movies. Another poll found that 46 percent of all Americans have engaged in piracy (Anderson). Back in the 1980s, music piracy was slightly spotted, when people created things called mixed tapes, however making these did not cost the industry much money. Cases of music piracy highly increased after the compact disc (CD) was created in 1982. One major case of music piracy was affiliated with the heavy metal band Metallica on April 13, 2000. Metallica filed a lawsuit against Napster due to many copyright infringements, and racketeering. The heavy metal band found $10 million worth of damages which is roughly $100,000 per downloaded song. NetPD evaluated Napster’s illegal program, and produced a list of 335,435 users that were downloading and sharing the band’s albums.
A Worldwide Problem Software piracy is defined as the illegal copying of software for commercial or personal gain. Software companies have tried many methods to prevent piracy, with varying degrees of success. Several agencies like the Software Publishers Association and the Business Software Alliance have been formed to combat both worldwide and domestic piracy. Software piracy is an unresolved, worldwide problem, costing millions of dollars in lost revenue. Software companies have used many different copy protection schemes. The most annoying form of copy protection is the use of a key disk. This type of copy protection requires the user to insert the original disk every time the program is run. It can be quite difficult to keep up with disks that are years old. The most common technique of copy protection requires the user to look up a word or phrase in the program's manual. This method is less annoying than other forms of copy protection, but it can be a nuisance having to locate the manual every time. Software pirates usually have no trouble "cracking" the program, which permanently removes the copy protection. After the invention of CD-ROM, which until lately was uncopyable, most software companies stopped placing copy protection in their programs. Instead, the companies are trying new methods of disc impression. 3M recently developed a new technology of disc impression which allows companies to imprint an image on the read side of a CD-ROM. This technology would not prevent pirates from copying the CD, but it would make a "bootleg" copy differ from the original and make the copy traceable by law enforcement officials (Estes 89). Sometimes, when a person uses a pirated program, there is a "virus" attached to the program. Viruses are self-replicating programs that, when activated, can damage a computer. These viruses are most commonly found on pirated computer games, placed there by some malignant computer programmer. In his January 1993 article, Chris O' Malley points out that if piracy was wiped out viruses would eventually disappear (O' Malley 60). There are ways that a thrifty consumer can save money on software without resorting to piracy. Computer companies often offer discounts on new software if a person has previously purchased an earlier version of the software. Competition between companies also drives prices low and keeps the number of pirated copies down (Morgan 45). People eventually tire or outgrow their software and decide to sell it.
CD burning enables any individual with the software and equipment to make a duplicate copy of any compact disc. Compact disks are also able to hold information, and this is a major advantage of burning technology. With the ability to burn information onto CDs, people are now able to make larger files and presentations and are not limited as much by storage space as they were when floppy disks were the only medium to transfer data between computers. The ability to transport large files is an advantage for many people: from students with large projects to do to business men and women who have major presentations to give. Now people are able to transport larger files w...
Toni Morrison's novel, The Bluest Eye contributes to the study of the American novel by bringing to light an unflattering side of American history. The story of a young black girl named Pecola, growing up in Lorain, Ohio in 1941 clearly illustrates the fact that the "American Dream" was not available to everyone. The world that Pecola inhabits adores blonde haired blue eyed girls and boys. Black children are invisible in this world, not special, less than nothing. The idea that the color of your skin somehow made you lesser was cultivated by both whites and blacks. White skin meant beauty and privilege and that idea was not questioned at this time in history. The idea that the color of your skin somehow made you less of a person contaminated black people's lives in many different ways. The taunts of schoolboys directed at Pecola clearly illustrate this fact; "It was their contempt for their own blackness that gave the first insult its teeth" (65). This self hatred also possessed an undercurrent of anger and injustice that eventually led to the civil rights movement.
In the novel The Bluest Eye by Toni Morrison, she exposes the suffering produced by the problems caused by gender and race oppression through the experiences of African-American children. During the 1940’s, the United States had composed an identity through mass media with books such as “Dick and Jane”, and movies like “Sherley Temple.” These media sources provided a society based on national innocence. In the novel, Morrison relates to and exposes the very real issues that were hidden by the idea of the stereotypical white middle-class family.
Emille Berliner invents earliest discs in 1889 and a whole new era of music distribution on replicate-able media can begin.
An unexpected twist, that Pecola’s bright, blue eyes would be the source of her blindness. Nothing pummeled at her mind more than her inexorable yearning for a physical trait exclusive to white culture. The porcelain-skinned children of storybooks taught her that beautiful, sparkling blue eyes were the golden key to beauty, and she retained this information well. She wasn’t the only one. Girls of colored skin have been pressured for years to strip themselves of their culture—mentally, emotionally, even physically—and not much has changed. Toni Morrison forces us to confront the formidable oppression pressed onto people of color by people void of it in her novel, The Bluest Eye.