The Thevenin equivalent resistance Essay Example

The Thevenin equivalent resistance Paper When using a voltage or current that varies, certain components that would not work with a direct current become functional. The capacitor is this type of component. It is made up of two conducting pieces of material that are a small distance apart and are separated by an insulator (or dielectric). The following experiments will show the way in which the capacitor works when placed in a working circuit in different combinations with a resistor. They will show how the time constant can be calculated experimentally as well as theoretically. One of the most underlying laws when dealing with electronics, which was introduced by Georg Ohm in 1821 [Gough], is Ohms Law. These experiments will validate this law. It will also investigate how the characteristics of a circuit may change when introducing resistors in parallel or series and as a result, verify the voltage divider rule. They will look at voltage drops around complete loops and how by manipulating a circuit can be used to make complex networks simpler, thereby validating Kirchoffs Voltage and Current Laws, and Thevenins Theorem. The Wheatstone bridge circuit was developed in 1843 by Charles Wheatstone in order to determine the values of unknown resistances [Gough], This will be investigated to check the validity of the Wheatstone bridge theory and prove its usefulness. Theory Experiment P-IE-R-1 (Ohms Law) Ohms Law indicates that the current through a conductor is proportional to the difference in potential between its ends. This, in equation form, is shown by V=I R (V is potential difference, I is the current and R is the constant of proportionality, or resistance). We will write a custom essay sample on The Thevenin equivalent resistance specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on The Thevenin equivalent resistance specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on The Thevenin equivalent resistance specifically for you FOR ONLY $16.38 $13.9/page Hire Writer So if a current is passed through a circuit with an unknown resistance, this resistance can be calculated by plotting a graph of voltage against current. This should produce a straight line with a slope equalling the value of R. Experiment P-IE-R-2 (Resistor Networks) If a number of components are connected so that the current through each of them is equal then they are connected in series. So if you have two resistors connected in series, as shown below in Figure 1, then V1 = R1 I and V2 = R2 I. If you total all the separate potential differences around the circuit in Figure 1, then the sum will be 0, this is true for any complete loop in a circuit. It is known as Kirchoffs Voltage Law. As a result of this, each value of resistance can be combined to give an equivalent resistance, referred to as Req, this has no effect on the characteristics of the circuit. However, the components within a circuit can be connected up so that the potential difference across each of them is identical. This is a parallel connection. The two resistors in Figure 2 show components in parallel. The current of each is given as I1 = V/R1 and I2 = V/R2. As charge is conserved, it can be said the amount of current going into a node is equal to the total amount that leaves it, i. e. the sum of the currents is 0 (This is known as Kirchoffs current law). Therefore, the amount of current that passes through the two resistors in Figure 2 has to be equal to the current that is generated by the supply. It can be expressed as I = I1 + I2. By manipulating this equation and applying Ohms law, the equivalent resistance of the circuit can be calculated using the following equation 1/Req = 1/R1 + 1/R2. But when there are only two resistors it can be written as Req = R1 R2 / (R1 + R2), this is known as the product over the sum rule. Experiment P-IE-R-3 (Kirchoffs Laws and Thevenin Resistor Networks) Kirchoffs Laws: As mentioned above, Kirchoffs Voltage Law is defined as The algebraic sum of the potential differences around any complete loop of a circuit is zero [Gough]. Therefore if you refer to Figure 1, V = V1 + V2. But as Figure 2 indicates, current flows into the positive side of a resistor but at the same time out of the positive terminal of an emf source. As a result potential difference can be called the Voltage Drop. Also mentioned above, Kirchoffs current law can be defined as the algebraic sum of the currents into any node is zero [Gough]. So where three or more conductors connect the total current through the node will equal the current from the supply. Referring back to Figure 2, this can be shown by writing I = I1 + I2. Thevenins Theorem Thevenins Theorem can be defined as any network of resistors and batteries having two terminals is equivalent, as far as its terminal behaviour is concerned, to the series combination of a resistor and a DC voltage supply. [Gough] With a Voltage divider (Figure 3), by moving the switch to certain possible connections, different fractions of the supply can be created at the output. So if the switch is connected to the point B as shown, the output voltage can be obtained using the formula Vout = I R3. The current can be calculated by first working out the total resistance of the circuit and then by using Ohms law. If a load resistance is put across the output terminals as shown in Figure 3, then the current in the circuit will no longer be the same. The new value for the current will now be obtainable by using the formula I = V (R3 + RL)/ RL (R1 + R2 + R3) + (R1 + R2) R3. If a load is connected across Vout, then the current through the load resistance will be given by IL = Vout/RL. This shows that by using a combination of Ohms law and Kirchoffs Current and Voltage Laws, more complex circuits can be analysed faster and more easily. Experiment P-IE-R-4 (The Wheatstone Bridge) As Figure 4 shows the unknown resistor is R4, the other resistances, apart from R5, are known and can be a combination of different values. This circuit works by varying the resistance of R1, R2 and R3 so that the current through R5 is equal to zero. When the circuit is in this situation the bridge is known to be balanced. The value of the unknown resistor can then be worked out by using the values of the now known resistors. By using Thevenins theorem the current through R5 can be found by changing the rest of the circuit to its Thevenins equivalent, this gives the circuit shown in Figure 5. The Thevenin equivalent resistance (RT) across DB is ascertained by connecting these two parallel resistor combinations across R5, giving the Formula: RT = (R1 R3/ R1 + R3) + (R2 R4 / R2 + R4) The Thevenin equivalent voltage is determined by measuring the potential difference between the points D and B without R5 connected. As there are two parallel combinations of resistors, the voltage through each of them will be equal. This Voltage will be equal to the one that is driving the circuit, i. e. V, therefore the equivalent Thevenin Voltage can be obtained by using the formula VT = VDB = V [(R1 / {R1 + R3}) (R2 / {R2 + R4})] So I5 can be worked out using the Thevenin equivalent Voltage and resistance along with R5. The bridge is balanced when VT is equal to zero.

Free Essays on Treating Aids- The Global Ethical Dilema

Treating AIDS- The Global Ethical Dilemma Statistics show that ninety percent of the world’s 33 million HIV/AIDS cases are in Africa, Latin America, and Asia. These areas are known to be much more deficient and therefore can not afford the drug to help fight AIDS. The quandary for the drug companies is how to make these drugs more inexpensive. These drugs are very much needed. 8 percent of the 38 million people in South Africa are infected with the AIDS virus. Western drug companies face issues of social responsibility in both short and long terms. Their short term responsibility is to deal with the pressure they are receiving from health organizations around the world, global competition, compassion for those unfortunate that can’t be treated, and to maintain a benevolent image. The long term responsibility the industry is faced with is maintaining sufficient revenue to support the goal of developing a cure for AIDS and other diseases. Along with getting the drug to everyone in need, the pharmaceutical industry is fighting to protect the patents on their drugs. Large companies are in business to invest numerous amounts of money to develop drugs. Patents protect the companies from generic copies. Without patents, businesses feel they would not survive. This would be a crisis for world health. This leaves us with the overall problem of who should pay for AIDS drugs around the world? In 1997, the South African government passed a law securing cheaper drugs for its people by allowing local companies to copy patented drugs. It also allowed the AIDS drug to be imported from other countries. By May 2000, five major companies offered to sell the AIDS drug at reduced prices to developing countries, although, various groups pressure the drug companies to reduce their prices even lower for poor countries. An Indian company, Cipla Ltd., announced in February 2001 that it would provide its generic version of the triple... Free Essays on Treating Aids- The Global Ethical Dilema Free Essays on Treating Aids- The Global Ethical Dilema Treating AIDS- The Global Ethical Dilemma Statistics show that ninety percent of the world’s 33 million HIV/AIDS cases are in Africa, Latin America, and Asia. These areas are known to be much more deficient and therefore can not afford the drug to help fight AIDS. The quandary for the drug companies is how to make these drugs more inexpensive. These drugs are very much needed. 8 percent of the 38 million people in South Africa are infected with the AIDS virus. Western drug companies face issues of social responsibility in both short and long terms. Their short term responsibility is to deal with the pressure they are receiving from health organizations around the world, global competition, compassion for those unfortunate that can’t be treated, and to maintain a benevolent image. The long term responsibility the industry is faced with is maintaining sufficient revenue to support the goal of developing a cure for AIDS and other diseases. Along with getting the drug to everyone in need, the pharmaceutical industry is fighting to protect the patents on their drugs. Large companies are in business to invest numerous amounts of money to develop drugs. Patents protect the companies from generic copies. Without patents, businesses feel they would not survive. This would be a crisis for world health. This leaves us with the overall problem of who should pay for AIDS drugs around the world? In 1997, the South African government passed a law securing cheaper drugs for its people by allowing local companies to copy patented drugs. It also allowed the AIDS drug to be imported from other countries. By May 2000, five major companies offered to sell the AIDS drug at reduced prices to developing countries, although, various groups pressure the drug companies to reduce their prices even lower for poor countries. An Indian company, Cipla Ltd., announced in February 2001 that it would provide its generic version of the triple...

Governments and the arts week 9 Assignment Example | Topics and Well Written Essays - 250 words

Governments and the arts week 9 - Assignment Example The programs were a good avenue for the citizens to be employed through displaying of their artistic skills. The average wage was roughly $75 per work. The Work projects Administration was a noble idea during the Great Depression. A number of writers were contracted by the government to record and document the historical moment. As a matter of fact, the Library Congress has got more than 2,900 articles from the Federal Writers’ Project and WPA. Through this project, 3,789 artists were hired thus reducing unemployment (Adler, 2009), something rare during a depression. The good thing with artists is, they actualize the real event as they happen. Through such projects, it was possible in improving the country’s language because it was the best avenue of sharing the vernacular speech. For instance the narrator of Invisible man used a series of philosophical questions thus providing a range option. The U.S. Government displays the artifacts in museums to make sure the culture is still evident to the current public. For instance, the use of graffiti on cars could not have been familiar in the present world if it was not displayed through art. President Franklin Roosevelt was a political and social star who came up with social programs that were of great benefit to the country’s citizens. While understanding the outrageous effect of racial discrimination at such times, the use of such programs helped in bringing equality since art expressed what each group wanted. In addition, it was a source of employment, which helped reduce the effect of the Great Depression. Adler Jerry. (2009, June). 1934: The Art of New Deal. Smithsonian magazine. Retrieved on 2nd Dec 2014 from:

Training and Development in UK Business Essay Example | Topics and Well Written Essays - 1750 words

Training and Development in UK Business - Essay Example This helps the organization to train the employee while they are still performing their duties. On-work training is one of the most effective ways of helping an organization to increase the skills of its workforce. However organization can also train their employees in other institution. In this case employees are given study leave to attend training in other institutions. This is usually important when organization want to train their employees on new technology which is not readily available. There are other benchmarked ways that have been shown to be important in the training and development of the workforce that can be used by organization (Arkin 1995, p. 73). Employees can also be trained on different issues. The kind of skills that the company imparts to its workforce depends on the line of operations. But there are general skills that any company will need to impart to its workforce including communications, customer services, respecting diversity in the workplace, ethics in operation, human relations, and others that are important in the functioning of the organization as one system. But the most important skills that any organization would like to impart of its workforce with the special skills that are used in its line of operations. However at the end of the day there ar... However at the end of the day there are number of benefits that both the employees and the organization are likely to have. Although the organization will use a lot of resource in training the employee, at the end it will have a competent workforce and increase its overall production. It will haves satisfied workforce and reduce its rate of employee turnover. It will also help to enhance the image of the company and help in risk management. For the employees, there will be increased job satisfaction, increase level of employee motivation, increase efficiencies in the production process, increase capacity for them to adapt to the new work processes and the new technologies that are being implemented in the workplace, increase innovation and reduced turnover (Beard 2002, p. 83).Most of the studies that have been carried out have shown that there is a difference between different companies in the way they train their employees and the achievement of the employees. In this case it has be en noted that companies may use the same training and development process but achieve different end results. While the quality and the level of train can be taken as a probable factor causing this difference, many studies have not looked the employee's contribution factor in the efficiency of the process. There is need to carry out more research on the different between employee expectation and perception of training and the overall success of training and development initiatives (Thorpe 1997, p. 23). Problem statement Although most companies have invested in the training and development of their workforces, they have not been achieving the same result. Studies have

There is a best time to eat fruits Essay Example for Free

There is a best time to eat fruits Essay The title of the article is â€Å"Fruit and vegetable consumption† by Claudio E. Perez, published under Health Reports, volume 13, issue number 3, last March 2002. This is a secondary data source that analyzes the first hand information from the first half of cycle 1.1 of the Canadian Community Health Survey, which was done starting from September 2000 up to February 2001. This article tackles on the various connections associating the frequency of consuming fruits and vegetables with other health-linked activities and situations like physical activities and exercises, smoking, drinking (alcohol consumption) and weight problems like obesity.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The research process that led me to this article was a series of database and search engine browsing and reading. Not all the sources that can be found in various databases are useful that’s why careful reading and analyses should be done. Using search engines like Google and Yahoo, I was able to come up with several articles when I keyed-in the words â€Å"best time to eat fruits.† The result turn-outs were overwhelming, but browsing through these outputs, there is barely any useful information that was available. The problems that have been encountered in looking for the article   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The problem with these search engines is that there are a lot of articles, but only a few are proven to be credible. Using articles which no has known credibility would just spoil the research process, since the information you have at hand may not be telling the truth. If that’s the case, then it would be useless since there is no real basis of the information that you have gathered. In my case there were some who are not credible, turnouts coming from blogs or written by anonymous authors prove no actual use in my search for the â€Å"best time to eat fruits.† What leads me to finding the right article I could use was when I searched an online database for research articles by professionals which have been used in a larger scale, like a national survey. I keyed in the keywords â€Å"best time to eat fruits† but there were no results that came up. I narrowed my query to â€Å"time to eat fruits,† until I came up with Claudio E. Perez’ article, â€Å"Fruit and vegetable consumption.† Evaluating the reliability of a source   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   When evaluating whether the source at hand is reliable, I looked into some considerations like when and where it was published, and if it came into public review at some time. The article by Perez was based on a survey across Canada from the Canadian Community Health Survey. It was about the fruit and vegetable consumption and its relation to important health-related factors like exercise, smoking, alcohol consumption and obesity all around Canada. Claudio Perez’ credibility has been strengthened with his association with the Health Statistics Division at Statistics Canada. This means that he is affiliated with the actual research and data gathering institution which proves that his articles are factual and are based on actual results from surveys and researches made by other people. This article by Claudio Perez was also published under a journal entitled Health Reports which was spread around the country. It was published around March 2002, and was included in databases in various college online libraries all over the country.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The reliability of this article is also strengthened with the information that it offers, coming from a survey done in Canada by a legal institution. Also, the articles he provided in this writings were also based on previous writings by credible sources, which he used to back his information. Because of this, he was able to come up with a credible facts and information that back can back up his article, thus providing credibility for his paper. Questions that the article need to answer and the argument that it supports   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   When looking for the best time to eat fruits, I also considered several factors. This includes the consumers of these fruits, the fruits that are going to be consumed and the form or state that these fruits could be consumed. Looking at the nature of fruits in the human beings diet, it is usually being consumed as a dessert, food that could be consumed to fulfill the cravings for something sweet. But considering that these fruits have existed even before the discovery of cereals as staple food, it means that man has consumed food in their basic diets, not only as a dessert, but as a staple food instead. It then answer’s the query on the real role of fruit in people’s lives: not only a dessert, but could also be a number one source of dietary supplements that the body needs.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Another query that this article answers is regarding the consumers of fruits. Basically, everyone needs to consume these fruits, since it is a good source of fiber and vitamins, something that could supply a good quality of sugar, an essential ingredient for the body’s energy. People from all walks of life should eat fruits, but this paper showed that not all of the people consume these foods. The most common consumers of these fruits come from middle to upper class people of the society, since they are the ones who are able to afford or be able to bring out extra money in their budgets to buy fruits. This is because of the fact that these fruits are not a staple food in people’s diets today, that’s why they would prefer to allocate their budgets to buy cereals and meat products as a part of their menu. They view fruits as a dessert, that’s why they would spend extra money on buying it, especially if they are a little short on the budget.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Another query is what should be the forms or the state that these fruits could be consumed. Since most of the people view fruits as something to be eaten for dessert, they are usually eaten raw or sweetened or turned into candies or confectionaries. Others consume fruits by â€Å"juicing† them up, especially the citrus fruits (Stoppani). Others prefer to turn them into blended shakes or frooties and drink them as is, especially for those who are on slimming diets, avoiding eating foods rich in fats.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The real argument that this paper needs to answer is about the best time to eat fruits, and according to this article by Claudio Perez, these fruits can be eaten anytime during the day, since it was considered before as a staple food, not just some desserts or appetizers. It could provide the essential vitamins and nutrients that the body needs, and even more. These fruits are considered one of the healthiest foods, and that consuming them at a raw state is highly encouraged. With the advent of technology, they are being turned into juices or something appealing to the senses, like the more palatable fruit shakes, mixed with milk and other sweeteners. Summary of the structure and content of the source   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Claudio Perez’ article. â€Å"Fruit and vegetable consumption,† aims to establish relationships and associations between various frequencies of consuming fruits and vegetable products with various health concerns like alcoholism, smoking, and physical activities and exercise. His data came from the Canadian Community Health Survey, wherein the data gathered were from September 200 through February 2001, the first half of the cycle 1.1. Population-based information and data regarding the fruit and vegetable consumption all over Canada were made available from the Canadian Community Health Survey. According to Perez, â€Å"Numerous studies indicate that a diet rich in fruits and vegetables may help to prevent cardiovascular disease and certain cancers, which are leading causes of death in Canada (Perez).† This article associated low frequency of eating fruits and vegetables with several health risks to the human beings. This includes physical inactivity, smoking, weight problems and alcoholism.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The analytical techniques that were employed includes weighted means of providing information regarding the frequency of eating fruits and vegetables as related to various health behaviors of human beings. These health behaviors include consumption of alcohol, physical exercises and activities, smoking and weight problems. According to Perez, â€Å"the effects of other influences on food choices were considered, the positive relationship between fruit and vegetable consumption frequency and chronic disease persisted for men (Perez).† Health status and socio-demographic characteristics were also weighed in, in relation to frequency of eating fruits and vegetables.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The results that he was able to come up was that women were the ones who consume more of these fruits and vegetables as compared to men. According to Perez, â€Å"The average consumption frequencies for men and women whose level of physical activity was moderate or active and for those who were not daily smokers were significantly higher than the respective averages for men and women who were physically inactive or who smoked daily (Perez).† Taking on other influences regarding the topic, this relates the consumption of these fruits and vegetables into the state of being physically active, not engaging in smoking, and the reduced occurrence of being overweight, and not becoming alcohol dependent. Another article coming from an online source   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   This article was written by Frederic Patenaude, a noted author of health books and articles, chef and health expert. His article, â€Å"Is there a food better than fruit?† is about the consumption of fruits not only for desserts and snacks but as a staple food in human diets(Patenaude Is There a Food Better Than Fruit?). This article is found on the Free Weekly Online Newsletter, Pure Health and Nutrition, wherein Frederic Patenaude was one of the main contributors. This article is a first hand source of information or a primary source, since it Patenaude shares what he knows regarding the topic. It was more of an analysis of fruits as a staple food, with historical backgrounds of the primary diets of people back in time mostly consisting of fruits and vegetables (Patenaude Raw Soups, Salads and Smoothies: Simple Recipes for Everyday Health). It provided a list of the benefits that is offered by eating fruits, like it is a good source of natural sugar which is a source of energy for the body. It is also a good source of vitamins for the body as compared to any food. References: Diamond, Harvey. Tips and Hints for Eating Fruit Til Noon .   2006. Fit for Life: Not Fat for Life Ed. Harvey DIamond.   eNotalone.com Inc. April 17 2007. http://www.enotalone.com/article/4153.html. Patenaude, Frederic. Is There a Food Better Than Fruit?   2006.   Pure Health and Nutrition E-zine. April 17 2007. http://www.fredericpatenaude.com/fruit-article.html. . Raw Soups, Salads and Smoothies: Simple Recipes for Everyday Health. Raw Vegan, 2003. Perez, Claudio E. Fruits and Vegetable Consumption. Health Reports Volume 13.Issue 3 (2002). Stoppani, Jim. The Ripe Stuff: Can You Ea T Fruit and Still Get Sliced? M F Experts Dissect This Dieting Question. Muscle Fitness   (2005).

Essay --

Herman Melville, one of the more iconic names in Gothic literature, saw the world differently. Free from the Puritan rhetoric, Melville very much enjoyed the pleasures of the natural world. Melville traveled, and spent time among Natives. In several accounts he described his favorable time amongst them, and showcased the idea of noble savages beyond the borders of America. Without such tragedy to fuel him, Melville penned optimistic stories of adventure and excitement. The world wasn't a trap or a test, but a rich pearl oyster to be pursued and celebrated. True fame, or at least legacy, came later, with the publication of Moby-Dick. A darker story, but still heavy with adventure, Moby-Dick was undoubtedly a story of tragedy. Ahab, the iconic captain in the story, was driven by an obsession to hunt down a whale that injured him years prior to the story's beginning. Rather than accepting this as nature being a bit dangerous Ahab, against the better judgment of other members of his crew , anthropomorphised the titular whale, seeing it as a someone, not something, that wronged him and des...

Fita Analyzation

I. Narrative structure â€Å"YES OR OO†, which is the word that would love the guy to hear from the girl he is courting, but there are times that the girls, means this in a more different way. And that’s what FITA commercial wants to show us with the use of their product. The story of the FITA commercial is about a suitor who doesn’t figure out that the girl he is courting, answered him already. And the story goes like this. . . The guy (suitor) fetched Claris, the girl he is courting in the gymnasium. He grabbed the bag of Claris and put it on his back, Claris saw the FITA biscuit in the pocket of her bag then she grabbed and opened it. While they are walking inside the gym, the guy started to whine over Claris and told her that he’s courting her for about 2 years and yet there’s nothing happened with their relationshipand said â€Å"kailan ko ba maririnig ang matamis mong oo? †The guy look back at Claris then she raised a two pieces of FITA biscuit in her hands while smiling at him and finally decide to accept the guys love thru showing him the biscuit, depicting OO, or YES. The guy just grabbed the piece of FITA and jut ate it and said that â€Å"naghihintay na lng ba ko sa wala? † So Claris frowned and just ate the FITA she’s holding. The commercial is a dramatic comedy in a way that when the guy didn’t get what Claris means by showing the 2 pieces of FITA. II. Characters â€Å"The next hottest love team in town† That’s what the 2 main characters in the commercial wants to portray. The leading man is the suitor named Arran Sese in real life that is good looking, stands 5’9†w /white complexion and a dark brown hair. In the commercial, he is a college student that’s somewhat 18 to 20 yrs. ld and he’s voice is natural and there’s no something strange about it but he speaks very well specially when he whined with Claris, acts as the leading lady, named Amanda Lapus in real life with an angelic face who stands 5’7†w/ a white complexion and a black shiny hair. Again in the comm ercial, Claris is the girl who is being courted by the guy. They did not directly advertise the product by saying that people should buy FITA; instead, they used it as props in the commercial. They help sell the products by showing humility that remarks in the mind of the viewers of what the guy did, that he didn’t get that Claris already means yes.