Lightning Essays - Electricity, Electrostatics, Spintronics

Lightning Lightning is a discharge of static electricity in the atmosphere, which causes a bright flash of light. When lighting goes through the air, it heats the air to degrees hotter than the sun's surface about 50,000 degrees fahrenheit. This heating causes the air to expand and contract. This causes the sound called thunder. Lightning is caused by a build up of negative ions in the atmosphere which discharges into the ground causing the negative ions to go with the positive ions in the ground. Static electricity is negatively and positively charged atoms. A static charge on the other hand is a individual atom with a negative or positive charge. There are three types of charges negative positive and neutral. Negative and positive ions attract. But two negatives repel each other, just like two positives will. Neutrally charged ions can attract to both negative and positive ions, because they have and balanced charge of negative and positive ions, this means it has the same amount of negative and positive ions. This is where the following rule is true "opposites attract, and likes repel." Static electricity is generated when two different objects are rubbed together and some electrons are stolen from one object and then start to collect on the surface of the other object. The object that loses electrons becomes positively charged, because electrons are negatively charged and there is an absence of electrons and too many protons. Now because opposites attract and like repel the reason hair stands up when you rub something on it can be explained. When something is rubbed in a dry place, the thing takes electrons from your hair, leaving your hair with a positive charge it stands up as far away as possible from the other positively charged hairs. There reason there is little static electricity in areas with a high humidity, like the Virgin Islands, is because the humidity in the air is a conductor of electricity, so it helps trancfer the free electrons to an area that can accept electrons, like the earth so not many free electrons stay on any object that is saturated. Static electricity can be use to do many things, one of these things is keeping down air pollution by putting an electrode in factory smoke stacks so that the dust will collect on the electrode. Lightning and static can be hazardous. lightning is harmful, some people think it does not have any threat from a distance, like when a lighting storm is up to ten miles away. The most lightning strikes take place under the lightning storm where the rain is raining the hardest. Signs to tell if lightning is going to strike in your area are, If your hair stands up you hear static popping or crackling, and if you feel you body tingle due to ions moving through your body the static on portable electronic things increases suddenly, you smell the smell of statically charged air, or you see static sparks sparking in the air around you. Things to do inside to keep from getting hurt while in a lightning storm are, get away from doorways outside, porches, windows, and good conductors of electricity. Avoid phones that are not cordless and if it is a cordless phone avoid it if it is on the cradle. Do not touch things that use electricity unless they are unplugged. Do not stand near or lay on concrete walls. Do not use a metal building for shelter. And don't go into the basement because the electricity can travel through the ground. To not get hurt outside, go inside if you hear thunder, if the sky looks threatening, and stay inside for at least 30 minutes after the last sound of thunder. If you are caught outside and do not have shelter close to you during a lightning storm, you should crouch to the ground, get onto the balls of your feet, put your hands on your knees, put your head between your knees, make yourself as small as you can, and try to have as little physical contact to the ground as you can. Static electricity has been known about for some time. Some time around the year 600BC the Greek Mathematician named Thales was might have been the first to record that amber rubbed with fur would attract small light objects. In 1733 C.F. de Cistenay Dufay named the two charges of static, resinous electricity due to too many electrons, and electron deficiency electricity. Now static electricity is discovered to be a source of many Lightning Essays - Electricity, Electrostatics, Spintronics Lightning Lightning is a discharge of static electricity in the atmosphere, which causes a bright flash of light. When lighting goes through the air, it heats the air to degrees hotter than the sun's surface about 50,000 degrees fahrenheit. This heating causes the air to expand and contract. This causes the sound called thunder. Lightning is caused by a build up of negative ions in the atmosphere which discharges into the ground causing the negative ions to go with the positive ions in the ground. Static electricity is negatively and positively charged atoms. A static charge on the other hand is a individual atom with a negative or positive charge. There are three types of charges negative positive and neutral. Negative and positive ions attract. But two negatives repel each other, just like two positives will. Neutrally charged ions can attract to both negative and positive ions, because they have and balanced charge of negative and positive ions, this means it has the same amount of negative and positive ions. This is where the following rule is true "opposites attract, and likes repel." Static electricity is generated when two different objects are rubbed together and some electrons are stolen from one object and then start to collect on the surface of the other object. The object that loses electrons becomes positively charged, because electrons are negatively charged and there is an absence of electrons and too many protons. Now because opposites attract and like repel the reason hair stands up when you rub something on it can be explained. When something is rubbed in a dry place, the thing takes electrons from your hair, leaving your hair with a positive charge it stands up as far away as possible from the other positively charged hairs. There reason there is little static electricity in areas with a high humidity, like the Virgin Islands, is because the humidity in the air is a conductor of electricity, so it helps trancfer the free electrons to an area that can accept electrons, like the earth so not many free electrons stay on any object that is saturated. Static electricity can be use to do many things, one of these things is keeping down air pollution by putting an electrode in factory smoke stacks so that the dust will collect on the electrode. Lightning and static can be hazardous. lightning is harmful, some people think it does not have any threat from a distance, like when a lighting storm is up to ten miles away. The most lightning strikes take place under the lightning storm where the rain is raining the hardest. Signs to tell if lightning is going to strike in your area are, If your hair stands up you hear static popping or crackling, and if you feel you body tingle due to ions moving through your body the static on portable electronic things increases suddenly, you smell the smell of statically charged air, or you see static sparks sparking in the air around you. Things to do inside to keep from getting hurt while in a lightning storm are, get away from doorways outside, porches, windows, and good conductors of electricity. Avoid phones that are not cordless and if it is a cordless phone avoid it if it is on the cradle. Do not touch things that use electricity unless they are unplugged. Do not stand near or lay on concrete walls. Do not use a metal building for shelter. And don't go into the basement because the electricity can travel through the ground. To not get hurt outside, go inside if you hear thunder, if the sky looks threatening, and stay inside for at least 30 minutes after the last sound of thunder. If you are caught outside and do not have shelter close to you during a lightning storm, you should crouch to the ground, get onto the balls of your feet, put your hands on your knees, put your head between your knees, make yourself as small as you can, and try to have as little physical contact to the ground as you can. Static electricity has been known about for some time. Some time around the year 600BC the Greek Mathematician named Thales was might have been the first to record that amber rubbed with fur would attract small light objects. In 1733 C.F. de Cistenay Dufay named the two charges of static, resinous electricity due to too many electrons, and electron deficiency electricity. Now static electricity is discovered to be a source of many

Motivational Theory and Generation Y

Motivational Theory and Generation Y Motivation theories explain about human nature and human needs. These theories demystify the nature of people and the forces that drive people into action. Motivational theory explains why people take the actions they take at work. These theories can be classified into organismic or mechanistic. Mechanistic theories view the human being as passive and needing prodding in order to take action.Advertising We will write a custom essay sample on Motivational Theory and Generation Y specifically for you for only $16.05 $11/page Learn More Organismic theories, on the other hand, view the human being as proactive and having initiative in his actions. The intrinsic needs and physiological drives of human beings account for this proactive nature. It is necessary to note that, at the work place, motivation is the result of incentives and human needs. A human being will feel more motivated when provided incentives meet his intrinsic needs. Motives are directed towards the achievement of a certain goal. Thus, the motives influence the behavior of the human being. Maslow’s hierarchy of needs is one of the theories that explains human motives as related to their needs. Maslow classifies human needs into five categories from the most pressing to the least pressing. It is also necessary to note that three of Maslow’s identified psychological needs are the most pressing needs for generation Y. These needs include basic human needs such as food, shelter and clothing. A person is not likely to start thinking of satisfying the other needs unless the psychological needs are met. Employees will desire a job that is capable of catering for and satisfying their psychological needs. Next in the hierarchy is a need for safety and security. Once his psychological needs have been satisfied, man will desire to ensure safety of the basic needs. People need to be sure of maintaining their status in the event of an unforeseen catastrophe. Members of an organization are likely to be motivated if their future is safe. If their future is in danger, persons will deem other things as unimportant. Again, people will work harder in life once they have satisfied their psychological needs in order to secure their future.Advertising Looking for essay on psychology? Let's see if we can help you! Get your first paper with 15% OFF Learn More Once safety and security needs have been met, social needs emerge as important. Man needs belongingness and recognition by the society. Employees will work harder to obtain outstanding results in order to gain belongingness and recognition in their organizations. In addition, organizations reward and recognize outstanding performance to motivate employees. It is worth mentioning that these three needs are the pressing needs in early adulthood. The needs of self esteem and self actualization arise much later in adulthood as Maslow explained. Douglas McGregor proposed two theories to explain the motivation in human beings. Theory X assumes that people are inherently lazy and need prodding in order to carry out a task. On the other hand, Theory Y assumes that people view work as play or rest. It is noteworthy that while some elements of generation Y require nudging in order to accomplish tasks, a number also like working independently and are self driven. Thus, the choice of which Theory to apply in motivating employees should not be made on a generalized approach but rather on an individual basis. Under Theory Y, McGregor proposed that employees should be given challenging tasks and involved in participative decision making. It is noteworthy that these are the same qualities that persons in early adulthood, commonly referred to as generation Y are seeking in their jobs. Consequently, to motivate the Generation Y, managers should be considering approaches that cater to their needs for recognition through active leadership opportunities, cash incentives and job en richment. In summary, approaches that best suit the needs of generation Y should be adopted. Leadership should cultivate trust and participatory leadership in the team. This will increase productivity in the team. The expectancy theory should be applied to ensure that reward systems award young adults with items they need. However, caution needs to be exercised to ensure that the extrinsic rewards given do not overshadow the need for the intrinsic drive to do work.Advertising We will write a custom essay sample on Motivational Theory and Generation Y specifically for you for only $16.05 $11/page Learn More

Using the 2 Simple Past Tenses of Spanish

Using the 2 Simple Past Tenses of Spanish English has one simple past tense, but Spanish has two: the preterite and the imperfect. The two past tenses refer in different ways to what has happened. They are called the simple past tenses to distinguish them from verb forms that use an auxiliary verb, such as has left in English and ha salido in Spanish. In other words, the simple past tenses use a single word. Although the English past in a sentence such as he ate can be conveyed in Spanish using either the preterite (comià ³) or the imperfect indicative (comà ­a), the two tenses dont mean the same thing. In general, the preterite is used when speaking of completed action, indicating the verbs action had a clear end. The imperfect is used to refer to an action that doesnt have a specific ending. Here are some more specific uses to clarify the differences between the two tenses. Note that the imperfect is frequently translated in ways other than the English simple past. Key Takeaways: Spanish Simple Past Tense Although English has one simple (single-word) past tense, Spanish has two, and they usually arent interchangeable.In general, the preterite tense is used for actions that took place over a clear period of time.In general, the imperfect tense is used for actions whose conclusion isnt irrelevant or unspecified. Uses for the Preterite Tense The preterite (often spelled preterite) is used to tell of something that happened once: Fuimos ayer a la playa. (We went to the beach yesterday.)Escribà ­ la carta. (I wrote the letter.)Compramos un coche azul.  (We bought a blue car.) It can also tell of something that happened more than once but with a specific end: Fui ayer seis veces a la tienda. (I went to the store six times yesterday.)Leyà ³ el libro cinco veces. (He read the book five times.) Finally, the preterite can indicate the beginning or end of a process: Tuvo frà ­o. (He got cold.)El huracn se terminà ³ a las ocho. (The hurricane was finished at 8.) Uses for the Imperfect Tense On the other hand, the imperfect tells of past habitual or repeated actions where theres no definite end specified. It is often translated as used to verb, would verb, or was/were verb -ing. Iba a la tienda. (I used to go to the store. Note that it is possible that the verbs action continues today.)Leà ­amos los libros. (We would read the books. The English would is sometimes used for the imperfect, as it is here, but it also is sometimes used for the conditional tense.)Lavaban las manos. (They were washing their hands.)Escribà ­a muchas cartas. (I wrote many letters.) The imperfect can describe a condition, mental state, or state of being from the past: Habà ­a una casa aquà ­. (There used to be a house here.)Era està ºpido. (He was stupid.)No te conocà ­a. (I didnt know you.)Querà ­a estar feliz. (He wanted to be happy.)Tenà ­a frà ­o. (He was cold.) To describe an action that occurred over an unspecified time: Se pondrà ­a la ropa de deporte. (She was putting on her athletic clothing.)Cuando Josà © tocaba el piano, Marà ­a comà ­a. (While Josà © was playing the piano, Marà ­a was eating.) To indicate time or age in the past: Era la una de la tarde. (It was 1 p.m.)Tenà ­a 43 aà ±os. (She was 43 years old.) Other Distinctions Between the Past Tenses The imperfect is frequently used to provide the background for an event that is described using the preterite. Era [imperfect] la una de la tarde cuando comià ³ [preterite]. (It was 1 p.m. when she ate.)Yo escribà ­a [imperfect] cuando llegaste [preterite]. (I was writing when you arrived.) Because of the way the two tenses are used, some verbs can be translated using differing words in English depending on the tense in Spanish. This is especially true when the preterite is used to indicate the beginning or end of a process. Conocà ­ [preterite] al presidente. (I met the president.) Conocà ­a [imperfect] al presidente. (I knew the president.)Tuvo [preterite]  frà ­o. (He got cold.) Tenà ­a [imperfect] frà ­o. (He was cold.)Supe [preterite] escuchar. (I found out how to listen.) Sabà ­a [imperfect] escuchar. (I knew how to listen.) Some of the sentences in this lesson could be stated in either tense with a slight change of meaning. For example, while Escribà ­a muchas cartas would be the typical way of saying I wrote many letters, as that is something that typically would take place over an unspecified period of time, one also might say Escribà ­ muchas cartas. But the meaning of the sentence, not readily translatable without a context to English, would change to indicate that the speaker was referring to a specific point in time. For example, if you were talking about writing many letters while you were on a particular trip, you might use the preterite form.

Tate Modern Essay Example | Topics and Well Written Essays - 1000 words

Tate Modern - Essay Example With the advent of technology it has entered the virtual world of internet and is working as a successful organization for the benefit of art and artists who are able to met their most potential buyers Rockefeller to Mittal who, consequently were the noted patron of the establishment. In general sense it could be stated that this establishment values customers who are educated and connoisseur of art. (Lamb, 2004) Louis Lozowick, Duchamp, Jackson Pollock, Myron Krueger, Anja Kroencke and ceramic artists like Peter Voulkos, Paul Soldner, Robert Arneson, Viola Frey and Bennet Bean are the most popular artists at Tate Moder. Among these noted artists Anja Kroencke holds a favorite position as this magnificent illustrator renowned for her outstanding fashion illustrations or more better said lifestyle illustrations. Her contribution in her field is commendable and her work includes the most identifiable masterpieces of illustrations. Anja Kroencke is well known for her distinct haughty women characters. The body proportion, body movement, faces, hands and feet, poses of the characters and the backgrounds in her drawings reflect high class, high profile modern society. Her characters (mostly women) are elegant, stylish and fashion trendy as seen from her drawings. The sophistication and the elegance of her lines and the zing in her works of art have given Anja Kroencke a distinct and remarkable po sition in the field of illustration. Her drawings are incredibly pure, playing with measured degree of black & white and color producing visible contrasts between wide stretches of pure white and vast regions of velvety shadows. (King, 2006) It should be stated that Jackson Pollock's Convergence is one noted favorite in this context. The most important point to be noted in this respect is the amount of energy that is reflected within the parameter of this 95" x 155" inch canvas. (Samuel, 1999) To ascertain a piece of canvas to be judged as a work of art it is necessary to evoke a certain feeling within the viewers. There is no grammar involved in this part; no mathematics is needed; only the artistic sense is operational in this context from the part of the viewer. The interpretation may vary but the theme that evoked the interpretation of the viewer is all that is important to certify a painting as Art. In this context too Jackson Pollock's Convergence comes out with flying colors. (Mitra, 1985) American ceramic artist Bennett Bean lives and works in Blairstown, NJ. Bean is primarily a studio potter but is also an equally good sculptor and painter. His trademark creations include pale pit-fired pots and vessels such as bowls and teapots. Bean has confessed to having been influenced by a range of ceramic art including Japanese pottery, English pottery (such as those by Bernard Leach) Native and Modern American pottery (such as those by George Ohr). Bean is also in the habit of using other beautifying techniques such as gilding and glazing on his pots, only instead of serving as decorative measures these methods help Bean in creating the kind of space and surface he is known for. The patterns he uses comes from a collection he has built up over 20 years, many of them are influenced by the

The trend in economic growth of a country Coursework

The trend in economic growth of a country - Coursework Example This essay discusses that throughout history there have been many studies on economic growth. Overall economic growth of a country is measured every year by the difference that has occurred in GDP over the previous year. Should we consider that a country grows only by analyzing the monetary value of the production of final goods and services during a period? In researcher’s opinion would have no sense not to consider the benefit that provides a trained workforce, or the economic stability of a country. To reinforce this idea the researcher will investigate past developments on this theory. Mincer elaborated a study about the relationships of the individual’s earnings as variable dependent in age, experience and education. Mincer considers that the benefits of education to the people can be extrapolated to countries. Considers that an educated workforce directly affects the growth of a country. He justifies that an extra year of education in a white man who did not work on a farm contributes a extra seven per cent of profit. Adam Smith was the first person that found some link between International Trade and Economic Growth. The work of Grossman and Helpman and Rivera-Batiz and Romer has also aided to clarify why the participation of a country in an integrated world economy can stimulate its growth. Oil production and exports affect economic growth. Limiting the supply of oil to a country can cause serious economic consequences. We must highlight the oil crisis of 1973 or the current threat from Iraq to the European Union countries to limit its supply. In relation to the political unrest, the IMF warned in its 60 years that a lack of political stability could affect economic growth.Regarding the number of murders; the current Mexican central bank governor Agustin Cartens (2011) said that violence inhibited economic growth. The model To begin with, we need to find the relationship between the dependent variables and independent variable (growth). Th e initial econometric model of the of this study is: y = ?0+ ?1(GRDP)+ ?2(TRADEHARE)+ ?3(YEARSSCHOOL)+ ?4(ASSASINATIONS)+ ?5(REV_COUPS)+?. Some of the coefficients are expected to negative because some of the figures of variables are greater than the figures in dependant variable. From the SPSS output table below us can note that there is a negative relationship between growth and rgdp60 as well rev-coups. This means that other factors help to increase growth as they have positive coefficients’. Coefficients Unstandardized Coefficients Standardized Coefficients t Sig. Model B Std. Error Beta 1 (Constant) .490 .690 .710 .480 RGDP60 -4.693E-04 .000 -.622 -3.167 .002 TRADESHA 1.562 .758 .238 2.060 .044 YEARSSCH .575 .139 .770 4.126 .000 RECOUPS -2.158 1.110 -.256 -1.943 .057 ASSIS .354 .477 .092 .742 .461 a Dependent Variable: GROWTH The model econometric model of the of this study will be y= 0.49 -0.00047(GRDP) + 1.561696 (tradeshare)+ 0.575 (Yearsschool)+ 0.354 (assassinations ) -2.1575 (rev_coups)+? Goodness-of-Fit Chi-Square df Sig. Pearson 232.676 4032 1.000 Deviance 188.381 4032 1.000 Link function: Logit. The goodness –of-fit- statistics for model is 232.6 this means that the data obtained from the random sample is greater than 5 thus it does not fit into a specific pattern. Model Summary Model R R Square Adjusted R Square Std. Error of the Estimate 1 .599 .359 .305 1.582084957 a Predictors:

Non-conventional Sources of Energy: An Analysis

Non-conventional Sources of Energy: An Analysis CONSERVATION OF ENERGY Energy is a primary input in any industrial operation. Energy is also a major input in sectors such as commerce, transport, telecommunication, etc besides the wide range of services required in the household industrial sectors. (A) What Do We Mean by Alternative Energy? The alternative-energy segment of the energy industry covers a broad range of sources. These sources range from well established technologies, such as nuclear energy and hydroelectric power, through high-growth segments such as wind and solar power. They also include less tried and tested alternatives, such as hydrogen-powered, fuel-cell technology for use in electricity generation (7) Renewable sources of energy: It is that energy which is renewed again again. These include wood obtained from forests, petroplants , plant biomass agricultural wastes, wind energy,water energy, geothermal energy, these can reproduce themselves in nature can be harvested continusiously through a sustained proper planning management(B) Non renewable sources of energy: These are available in limited amount develop over a long period of time. They are exhausted one day.these include coal,oil,petroleum, the common source of energy being organic in their origin also called fossil fuel.( B) Conventional source of energy: In most of the fuel wood was consumed for domestic purposes mainly in rural areas, very little of it was available to industrial sector. Coal already in use in industries become a highly priced source. It was then supplemented by mineral oil. Likewise the use of hydro-electricity become dearer the areas where running water needed technology was readily available. After 2nd world war nuclear power was developed. All these sources of energy. All these sources of energy are known as conventional sources of energy. Coal still occupies a central position. (B) Non conventional sources of energy: Non renewable of energy could exhaust one day. Most non renewable sources cause environmental pollution We must conserve non renewable sources by replacing with renewable sources. (B) CONSERVATION OF ENERGY Renewable sources of energy: Non renewable sources of energy: Conventional source of energy Non conventional sources of energy Sources of ener Sources of energy: Primary Secondry 1: primary sources are those which we get from environment.Eg. fossil fuel, nuclear fuel, hydro energy, solar energy, wind energy. 2: secondry sources are those which are derived from primary energy resource. Eg. Petrol, electrical energy, coal burning . (A) Conventional sources of energy: Coal: The heat capacity can be converted into the electricity gas , oil. therefore many thermal super thermal powerstation are located on the coal fields to produce electric power to feeds regional grids.(A) Oil : it was formed more than 300 million year ago. Tiny diatoms are the source of oil. Diatoms are the sea creature in the size of pin head. Diatoms are dead they fell into the sea floor. They buried under the rocks. The rock squeeze the diatoms the energy in the bodies could not escape. The carbon eventually turned into oil under great pressure heat. Oil natural gas are found under ground between rocks in areas where rocks are porous.(C) Natural gas: It is lighter than air . It is made up of methane (made up of carbon hydrogen atoms ch-4). It is found near the petroleum under the earth. It has no odour.it is usually mix with a gas that has strong odour like rotten eggs.(C) NUCLEAR FUSION If light nuclei are forced together, they will fuse with a yield of energy because the mass of the combination will be less than the sum of the masses of the individual nuclei. If the combined nuclear mass is less than that of iron at the peak of the binding energy curve, then nuclear particles will be more tightly bound than they were in the lighter nuclei, and that decrease in mass comes off in the form of the energy according to the Einstein relationship. For elements heavier than iron, fission will yield energy. For potential nuclear energy sources for the Earth, the deuterium-tritium fusion reaction contained by some kind of magnetic confinement seems the most likely path. However, for the fuelling of the stars, other fusion reactions will dominate. (c) NUCLEAR FISSION The nucleus captures the neutron, it splits into two lighter atoms and throws off two or three new neutrons. The two new atoms then emit gamma radiation as they settle into their new states. There are three things about this induced fission -the probability of a U-235 atom capturing a neutron as it passes by is fairly high. -the process of capturing the neutron and splitting happens very quickly, in the order of picoseconds -An incredible amount of energy is released in the form of heat and gamma radiation, when a single atom splits. The two atoms that result from the fission later release beta radiation and gamma radiation of their own as well. The energy released by a single fission Comes from the fact that the fission products and the neutrons, together, weigh less than the original U-235 atom. The difference in weight is converted directly to energy at a rate governed by the equation e=mc2 (C) NUCLEAR REACTOR (1)Light water reactor-We use ordinary water for colling and moderisation these are basic 2 types boiling water reactor pressurised water reactor There are also high temperature gas called reactors which basically of l.w.r type (2):heavy water reactor: the most popular one has been Canadian deuterium uranium reactor. The design is difficult from that of lwr type. The fuel is arranged horizontally rather than the vertically as in l.w.r. (3):liquid metal fast breeder reactor: here we use liquid sodium as the coolent. There are 300 atomic power plant ,operating in world. Max in use (83), Ussr (40), up (35), France(34),Japan 25, Germany 15, Canada 13 India is rich in atomic mineral. Uranium mines are located in singbum in bihar parts of bihar Most abudent source is monazite sands on the shores of kerala. Thorium is derived from these sands. Nuclear power corporation is engaged with the establishment of nucleus. Power plants: 6 nuclear power plants in operation generating 1230 mwe(single individual plant is 210-235mwe). (b) Advantages Nuclear energy has a number of positives going for it. First, it does not give off carbon emissions, earning it supporters in the environmental community among those concerned about global warming. second, once reactors are built, it is very cost effective to keep them running at high capacity and for utilities to address demand fluctuations by cutting back on usage of fossil fuels. Third, nuclear plants tend to last a long time and many existing plants have become more efficient over time, reducing their demand for uranium.and represent reliable sources of supply Disadvantages There are a number of disadvantages to the nuclear-power option. These include not only the safety questions but also some economic and supply-related questions that are currently being debated by those for and opposed to renewal of outdated power plants or an expansion of the sector.In terms of safety, two issues are regularly debated. First, the issue of nuclear waste and, second, concerns over potential terrorist attacks on nuclear power plants. The first objection may be overcome through the introduction of new types of power plants, such as the pebble-bed modular reactor. This type of reactor uses graphite balls flecked with tiny amounts of uranium, rather than conventional fuel rods. With the fuel encased in graphite and impermeable silicon carbide, the theory is that the waste should be relatively easy to dispose of. The terrorism fears are less easily addressed and may ultimately stall the construction of new plants in countries such as the U.S., where these worries are great est. Among economic concerns is the question of construction costs. Although the cost of energy produced by existing nuclear plants is competitive, the upfront capital costs of constructing new plants are extremely high, calculated at $1,300-$1,500 per kilowatt- hour, or twice the amount it costs to construct a gas-fired power station(F) Non Conventional energy source SOLAR ENERGY Two weeks of solar energy is roughly equivalent to the energy stored in all known reserves of coal.oil and natural gas on the earth. Solar energy may be directly used either by active solar system or passive solar system. Another potentially important aspect 0f direct solar energy involves solar cells or photovoltaic that convert sunlight directly into electricity. Two other type of solar energy are the solar power tower and solar ponds.(b) There are two main ways to harness the power of the sun to generate electricity: photovoltaic (PV), where sunlight is directly converted into electricity via solar cells, and solarthermal power. PV is a proven technology that is most appropriate for small-scale applications to provide heat and power to individual houses and businesses. Sunlight falls on a layer of semiconductors, which jostles electrons. This, in turn, creates an electrical current that can be used as a source for heat. Solar PV cells are already cost effective for powering houses and businesses in some regions. As with wind power, technological developments have reduced costs considerably over the last few years. Unlike wind power, however, largescale electricity production using solar energy costs about 22 cents per kilowatt-hour, significantly more expensive than its fossil fuel competitors and nuclear energy. Hopes to reduce these costs lie with newer technologies. Solar-thermal generated energy is only just emerging from the experimental stage to full-scale electricity production. Solar-thermal power concentrates the sun to heat up fuel such as gas or oil. The heat trapped within is then used to convert water into steam, which powers a conventional steam turbine to generate electricity. Fossil fuels are sometimes used as a back-up to heat the water in the boiler if the sun is not shining. There are three different methods for concentrating the suns rays: Parabolic Trough — This method uses long, parallel rows of glass mirrors in the shape of a trough to concentrate the suns rays toward the â€Å"absorber tube† — usually filled with oil — to maximum effect. Power Tower — Similar in principle to parabolic-trough technology, the mirrors are placed in a circular pattern. At the center of the circle is a tower, at the top of which is a receiver filled with water, air, liquid metal or molten salt that moves to a power block and is used to power a steam turbine. Parabolic Disk System — In this system, dishes rather than troughs are used to concentrate the power of the sun. An example of this type of solar project is the 500-megawatt Solar Energy Systems plant being constructed in the Mojave Desert in California. By the end of 2006, the company expects to begin supplying electricity to Southern California Edison (SCE), but will not be fully operational until 2011, when it may account for as much as a 20 percent increase in SCEs electricity generation from renewables(F) Advantages In spite of its cost versus other sources of energy, solar power is attracting interest due to the following: Solar energy makes use of a renewable natural resource that is readily available in many parts of the world. The process used to generate solar energy is emission-free. Technological advances have reduced costs to a point that it can compete with fossil fuel alternatives in specific circumstances. The technology is scalable in that it can be used fordomestic heating purposes or on a larger scale for commercial electricity generation, as solar water heaters are an established technology, widely available and simple to install and maintain Disadvantages The biggest barriers to increasing solar power generation are the cost, the amount of land required for large-scale electricity production, and the intermittent nature of the energy source.In terms of the latter, thermal systems do not work at night or in inclement weather. Storage of hot water for domestic or commercial use is simple, needing only insulated tanks, but storage of the higher-temperature liquids needed to generate electricity on a large scale — or storage of the electricity itself — requires further technological development(F) WIND ENERGY In the country there are areas which are quite windy. Wind energy may be converted into mechanical electrical energy. Now, wind has been utilized for pumping water in rural areas. Wind energy is useful in remote areas helps in saving fossils fuels, would deliver on the spot small quantity of energy which is free pollution environmental degradation.Gujrat is first to starts using wind power. Advantages There are a number of notable advantages associated with wind power: It is a clean, renewable energy source. There is no fuel component, so once built there is no a finite fuel supply or costs associated with such a supply. Wind power can be generated in remote areas, including out in the oceans. It is scalable in that it can be used to generate power in a local area or even at the individual property level, but can also generate large amounts of power that can be added to an electricity grid system.. For land-based wind farms, once the wind towers are installed, the land area around them can be used for other purposes, such as agricultural use. Disadvantages As with any source of energy, there are some drawbacks to wind power. The most significant is that the wind to drive the turbines may be intermittent and that it does not always blow when electricity is needed. Wind energy may only be available 40 percent of the year in some areas versus 90 percent for a fossil-fuel powered plant. New blade design can overcome this problem to a certain extent, as can storing the energy in batteries, but because of these potential drawbacks, the site of the wind farm is key to its success and vice versa.(F) OCEAN ENERGY (TIDAL ENERGY) Tidal power generation depends on the harnessing of rise and fall of sea level due to tidal action. Small tidal power plants have been constructed in china USSR. The most important application of tidal power is electricity generation. In India sites exploitation of tidal energy are gulfs of kutch kombay sunderbans. India could intensify work on ocean thermal energy conversion wave energy. The country is already experience with exploiting tidal energy. The central electricity authority Gujrat electricity board carried out site studies for establishment of tidal plants in golf of kutch. India has excellent OTEC potential some of the best sites in world are known to be located off the Indian mainland island of lakshdeep Andoman nicobar. Total OTEC potential in India is 50000mW which is about 150% of installed power generated capacity in India. PRESENT USES Tidal power has on a small scale been used throughout the history of mankind. It was not until twentieth century that large-scale tidal projects were considered. Today, sites suitable for the utilisation of tidal power exist in many places around the world. DISADVANTAGES -Not yet economically feasible. -Problems with transportation of hydroelectricity. -Technology not developed. ADVANTAGES -Renewable resource. -No pollution. -Produced 24 hours a day and 365 days a year. -Peak output coincides with peak energy demand.(c) Fuel cell Production of electricity by thermal plants is not a very efficient method and is major source of pollution. It now possible to make such in which reactants sre fed continuously to the electrodes and products are removed continuously from the electrolyte compartment. Galvanic cell that are designed to convert theenergy of combustion of fuels like hydrogen, methane, methanol,etc. directly into electrical energy are called fuel cell. One of the most successful fuel cell uses the reaction hydrogen with oxygen to form water. The cell was used for providing electrical power in Apollo space programme. The water vapours produced during the reaction were condensed and added to the drinking water supply for the astronauts. In the cell, hydrogen and oxygen are bubbled through porous carbon electrodes into concentrated aqueous sodium hydroxide solution. Catalyst like finally divided platinum metal are incorporated into the electrodes for increasing the rate of electrode reaction. Efficiency is 70%compared to thermal plant whose efficiency is 40%.(E) A fuel cell that runs on pure oxygen hydrogen produces no waste product. when a reformer is coupled to the fuel cell some pollutant are released(co2)but levels are typically less than conventional fossil fuel combustion in a power plant or an auto-mobile engine.fuel cell could be ideal zero emission power source for vehicle. Fuel cell busses could be tested in a Canada. The current from a fuel cell is proportional to the size of electrode voltage is limited (1.23). Tiny fuel cell running on methanol might used in cell phone, pager, toys, computer, now run by batteries. Bio fuel: based on fuel derived from organic biomass from recently living animals or plants or their by products, has transformed from a niche alternative to fossil fuels (e.g., gasoline, diesel) to become a booming industry. Any liquid that stores energy, which is typically utilized by an engine or generator, can be called a â€Å"fuel.† The term â€Å"bio fuels† encompasses a wide range of fuels, including vegetable oils, animal fats, ethanol, biodiesel (any oil or fat that undergoes trans esterification to more closely resemble mineral-based fuel), and syn fuel (fuel made from gasi fied organic matter, then liquefied to form fuel). The main common trait of all these fuels is that they are derived from organic biomass, rather than minerals. Bio fuels are made using a fairly simple process that typically involves harvesting feedstock, or the raw materials (e.g., soybeans, sugarcane), crushing the feedstock, separating the dry matter from the oil, then re-crushing and/or further processing to extract as much oil as possible. The resulting oil can then either be directly consumed (e.g., by vehicles with specially designed engines), further processed (e.g., into biodiesel), or blended with mineral-based fuel before being delivered to the end user at gas stations and depots around the world (the most common blends in the U.S. are E10 (10% percent ethanol blend) and E85 (85% ethanol blend). Only some biofuels, most notably biodiesel, can be used in traditional internal combustion engines. Other biofuels, such as ethanol, must be blended with mineral-based fuel in order to be used in existing engines. The most common inputs into biofuels vary by country. In the U.S., corn and soybeans are most prevalent, while Europe tends to use flaxseed and rapeseed, Brazil sugarcane, and Asia palm oil. Brazil is in many ways the pioneer of the biofuels industry, having introduced ethanol from sugarcane (and flexfuel vehicles capable of running on ethanol) over 25 years ago as method to reduce dependence on oil imports. a fuel cell uses a catalyst to create a reaction between hydrogen from a fuel and oxygen from the air to generate electricity, with the only byproduct being water. Such fuel cells can be used for power generation and as a replacement for the combustion engine to run cars and other vehicles. Fuel cells have long been used in the U.S. space program, but until the past few years have proved prohibitively expensive for civilian use. Interest in fuel cells was reignited in the late 1990s, as companies began to make breakthroughs in technology. Large automotive manufacturers, such as General Motors and Daimler Chrysler, also started investing in fuel-cell companies and began to design concept fuel-cell powered vehicles. Development, thus far, has focused primarily on protonexchange membrane (PEM) fuel cells. This type of fuel cell uses a polymer membrane to separate two subcells, one fed with hydrogen and one with oxygen (through air). On the hydrogen side, the hydrogen breaks down into pr otons and electrons, and the protons migrate through the membrane into the oxygen side. The electrons, on the other hand, are forced to detour through wire connecting metal plates, resulting in a reaction that creates electricity. Other types of cells include the molten-carbonate fuel cell, which is the most efficient design but is very complex and only economical when generating more than 200 kilowatts. Westinghouse is developing a competing design, the solidoxide fuel cell, which operates at extremely high temperatures and has the added advantage that waste heat can be used to drive an auxiliary gas turbine.(F) What are the Challenges to Large-Scale Hydrogen Production? One of the biggest challenges to moving towards large-scale adoption of the â€Å"hydrogen economy† is production of hydrogen itself. A question often raised is whether it takes more energy to produce the hydrogen than you get back when you either drive the car or use it to power a building. There are currently three ways to produce hydrogen: Natural gas, coal, wood and organic waste burn with air and steam at extremely high temperatures. When cooled, the resulting gases contain a significant amount of hydrogen. An electrical current is passed between two electrodes (anelectrolyzer) immersed in water. Hydrogen rises up from the negative electrode and oxygen from the positive electrode. Some bacteria reportedly produce hydrogen, but this method has yet to be exploited commercially The first of these options has traditionally been the most cost-effective. That it still requires the burning of fossil fuels, combined with the rising price for natural gas, however, makes it less attractive as a long-term solution. The second option is simple to establish and can be done on a small or large scale nearest the point where the hydrogen may be needed. However, it also has a major drawback. Although this method has a 98 percent efficiency rate, when you factor in the voltage of the fuel cell, you get back only 40 percent of what you put in There are two powerful arguments for converting electricity into hydrogen, in spite of the inefficiency of the process: The first is the â€Å"use it or lose it† principle. Electrical power itself cannot be stored in its pure form; it needs to be converted to something else. Just as surplus nuclear and gas-fired power stations may store unused power by using it to pump water back up inside a damper as part of an integrated electrical storage system in combination with a hydroelectric power plant, hydrogen can be similarly used to store unused electrical power. Second, electricity stored as hydrogen is versatile. Not only can it be used for re-electrification, it also can potentially be used as fuel for cars or for producing heat. Why Fuel Cells? Fuel cells directly convert the chemical energy in hydrogen to electricity, with pure water and potentially useful heat as the only byproducts. Hydrogen-powered fuel cells are not only pollution-free, but also can have two to three times the efficiency of traditional combustion technologies. A conventional combustion-based power plant typically generates electricity at efficiencies of 33 to 35 percent, while fuel cell systems can generate electricity at efficiencies up to 60 percent (and even higher with cogeneration). The gasoline engine in a conventional car is less than 20% efficient in converting the chemical energy in gasoline into power that moves the vehicle, under normal driving conditions. Hydrogen fuel cell vehicles, which use electric motors, are much more energy efficient and use 40-60 percent of the fuels energy — corresponding to more than a 50% reduction in fuel consumption, compared to a conventional vehicle with a gasoline internal combustion engine. In addition, fuel cells operate quietly, have fewer moving parts, and are well suited to a variety of applications. How Do Fuel Cells Work? A single fuel cell consists of an electrolyte sandwiched between two electrodes, an anode and a cathode. Bipolar plates on either side of the cell help distribute gases and serve as current collectors. In a Polymer Electrolyte Membrane (PEM) fuel cell, which most promising for light-duty transportation, hydrogen gas flows through channels to the anode, where a catalyst causes the hydrogen molecules to separate into protons and electrons. The membrane allows only the protons to pass through it. Comparison of Fuel Cell Technologies In general, all fuel cells have the same basic configuration — an electrolyte and two electrodes. But there are different types of fuel cells, classified primarily by the kind of electrolyte used. The electrolyte determines the kind of chemical reactions that take place in the fuel cell, the temperature range of operation, and other factors that determine its most suitable applications.(7)

Is Sharing Caring or Not Essay

Want to wear Gucci for a day? or maybe own a Ferrari for a week? Wondering how? Just like how you rent DVDs with a slight modern touch to it, mobile technology(you should have seen this coming) Can’t believe it? The future beholds us the sharing economy. What is the sharing economy? BBC defines it as â€Å"Everything from cars, central city parking spaces and designer clothes to accommodation are available from individuals and companies that are making billions from providing easy access to what people need in a difficult economy. However let me make one aspect very clear, this isn’t just all related to saving money (I know it is surprising in a money minded world like ours. ) Apart from helping people live in unstable economic conditions, some of those already using such an economic structure are utilizing it to conserve resources and save the planet. It will help you feel like a â€Å"better† person by saving the community taking simple small steps. You don’t want to own all those fancy electronic equipment in your households and not use it. Simply, hire one when you need it! In this technological age where you don’t know what to expect tomorrow (maybe your mobile generating a visual image in the air, it is very likely that â€Å"tomorrow† might apply in the literal sense here) you can use the sharing economy with transactions that can be made quickly through a cell phone app or a web site. This is very convenient and accessible at the same time. Wait a minute†¦ This looks too good to be true. Wondering what the drawback is? 2012 looked galaxies away for retail outlets in the world. However now, it looks like the doomsday for massive retail outlets is closing by. In simple words, the end of consumerism. If consumers can hire almost anything they want what will happen to retailers, what can they sell? It is obvious that this won’t be seen as a rapid change, but the effects can definitely be seen in the long term. Here is a fun fact,†Researchers say that we only use our cars eight per cent of the time and we spend billions on the space where we store stuff that we almost never use, such as power tools. They also say the sharing economy is expected to be worth $110 billion within the next few years. â€Å"No Pain. No Gain. † Consumers can get items for cheaper exactly when they require it conveniently, but lose jobs at the same time. It is time for every company to gear up, hire IT wizards, and make their e-commerce absolutely world class. The day you want to ride that Bentley or rent the finest villa for a day to spend with your family isn’t far.