Geology Essay Example | Topics and Well Written Essays - 250 words - 8

Geology - Essay Example The calcites are usually transparent or opaque and have traces of phosphorescence and/or fluorescence hence when used to view objects, they appear double. This is why its use for optical purposes. It occurs naturally owing to the marine decomposition of hard planktons like red algae, echinoderms, and sponges and it is found in limestone, volcanic, kimberlites, sedimentary or peridotites. It is used especially in military for in gun sights .It has also agricultural uses like stabilization of soil and concrete repair. Marcasite or white iron pyrite is a product of iron (Fe) and sulphur (s), to form Iron sulfide (Fes3). It has black metallic appearance and changes to brown or yellowish color. Its occurrence is primary or secondary in nature. Primarily, it occurs in highly acidic and with low temperatures conditions, mainly on sedimentary rocks or hydrothermal veins. In secondary, it is formed on alteration of chemicals of a parent mineral such as chalcopyrite. It reacts in high humidity to form iron (II) suphate and sulphuric acid. It is used mainly used for ornamental purposes and a source of sulphur. Galena is the natural form of the mineral lead sulphide and is the main ore for both silver and lead. It is also called lead glances and distributed widely on the sulphide minerals. It is mainly used to make lead- acid batteries, lead sheets and

Education by Computer - A Better Way Essay Example | Topics and Well Written Essays - 1000 words

Education by Computer - A Better Way - Essay Example It is easy for a student in America to take lectures from an Indian teacher now with the help of videoconferencing like computer technologies. Moreover, no other resources can provide the same referencing facilities as computer does. Instead of academic libraries, students now started to access online libraries in order to get more insights into a particular topic. Even though the utility of computer in education is unquestionable, some people argue that education by computers should not be encouraged beyond certain limits. This paper analyses whether education with the help of computers is good or bad or up to what extent we can rely on computers to provide better education to children. To be able to put the computer in an adequate perspective in education or in individual or social life it is necessary to understand very well what it is. Its main characteristic is that it is an abstract and not concrete machine (as, e.g. a power lathe or a bicycle): it acts in a virtual space, the space of the thoughts we may insert into the machine. So any use of it forces some abstract thinking (Setzer). Many people have the false belief that computers can bring wonders in educational circle. However, it should be noted that computers are working on artificial intelligence and it do not possess any natural intelligence as man possesses. In other words, computers are working based manmade instructions or programs. Since computers do not have the thinking ability, it cannot answer a question which is unfamiliar to it. On the other hand, human intelligence can try to solve all problems because of its independent thinking ability. According to Roger J. Desmond, a professor in the School of Communication at the University of Hartford, who specializes in kids and interactive media "computer games can increase reaction time, which can help with doing stuff that school requires†(Wood). Majority of the computer games encourage children to think in multiple ways to solve a part icular problem created by the computers. For example, Prince of Persia is a multilevel computer game popular among kids. This game presents so many puzzles in front of the kids. It is impossible for children to go to a higher level if they fail to solve the puzzle in the present level. Thus, they will be encouraged to think too much while playing Prince of Persia like computer games which is good for them to solve problems in their studies. Some people believe that over exposure to computer related education may damage the thinking abilities of the children. Learning is actually occurs through problem solving method. In other words, when a student tries to solve a problem, he will think about various ways to solve it. Thus he may develop so many hypotheses initially and test all of them with the help of trial and error method before arriving at the right solution. In short, self-solving of problems may help a student to open up many of his hidden faculties of mind which is good for the brain development. On the other hand, when a student tries to solve a problem with the help of computers, he is getting ready made answers at once and therefore he may not get an opportunity to give some kind of exercises to his brain. In short, over reliance on computers for solving problems can affect the thinking abilities of the students. It is a fact that many of the modern students are struggling while they are forced to take some critical decisions in their lives.