Constantan and Copper Essay Example for Free

Constantan and Copper Essay This crystalline therefore will not be able to hold the amount of stress which will be exerted by the weights slowly being added on; however we can predict that the copper element will face much stress and therefore will experience necking as the atoms as shown in the diagram will dislocate the atoms and therefore they can slide past each other more easily, consequently resulting in the fracture of the material. Copper is generally by itself very weak that is why it needs to be hardened and strengthened for many industrial applications. It is therefore mixed with other metals and melted. When carrying out this experiment I deem that as the number of weights is increased for copper, this will slowly exert pressure and the molecules will slowly pull apart as the bond will break between the molecules. The material will reach its elastic limit, where it has reached its point where by after if any more weights are added then it will deform and not return to its original state. Here is a diagram below which illustrates this: (Image extracted from physics textbook) The equations that I will acquire in this investigation to find out the aim, which is to find out youngs modulus of both materials through drawing of the graphs from the results I will need to use the following equation as this is what will aid me achieve this part of the aim: From my graphs, I will find out the gradient and therefore be able to work out youngs modulus by the formulae above. I believe that youngs modulus for constantan will be high because I consider from the evidence provided that it will be able to take more strain then the copper (crystalline). I deem this simply because constantan being an alloy can take more of a load then a pure metal. Here is a typical example of a stress train graph: (obtained from my physics textbook) Fair test:   Test the wire to get an average; I will do this three times. All of my figures will be to three significant figures.   I will carry this out on the same day in the same conditions, using all of the same apparatus. I will keep the metre stick stuck down to the table and not move it, so that it wont affect my results, when marking off the extension. Apparatus: I will be using the following:   Pulley   Metre ruler and a marker   Mass weights and actual storage unit   Wooden blocks to hold the wire in place   A G clamp. Safety: I will ensure that I keep this a safe experiment by: Keeping the cardboard over the wire, as when the wire snaps the wire would not suddenly lift up and cause any danger.   I will also make sure there are not people crowding the experiment when it is being carried out, as the weights can cause danger if they fall. Results: I have entered the results I have been given into Microsoft excel. From this the extension I have been given, is given in mm, but in physics we have to convert mm to metres. From the materials given I would find out the area of the wire as the area can depend on the wires, as they can have different thicknesses. Diameter: 0. 37mm The cross sectional area: pi r^2=1. 07510-7m2 To find the out the cross sectional area I simply had worked out the radius, which was 0. 000185, I achieved this figure by dividing the diameter (0. 37) by 2000. By calculating this I was left with this figure. I will need to find out stress over strain which will give me youngs modulus. Since the length of the wire is 2. 1metres this will be used to find out the strain. Here are my results for copper: Here is my table of results showing results from the copper wire. I have worked out the stress and strain which therefore simply allowed me to work out the youngs modulus of copper, and this I have shown on the computer. I have also shown the table showing the formulae I had input in the cells in Microsoft Excel. I have shown this below, in the last four columns where I had input the formula into the cells to aid me to work out youngs modulus of copper. I have shown the results I had obtained for copper above, now I will produce a table showing the results I achieved for constantan the alloy which I believe would have a higher youngs modulus then copper. I had used the same length of wire which is 2. 1metres as I made sure this was a fair test when conducting the experiment. I have worked out the cross sectional area as the same in the procedure before. Here are my results for constantan: Diameter: 0. 3510-3 Area: p r^2:9. 621010-8 m2 Here are my results stated above showing the results from the constantan wire. The results show the youngs modulus for constantan at the given force. Below is the formulae table showing the formulae which were input into the cells from stress and strain. When simplifying these results it will be evident I belie that the constantan wire will have the higher youngs module, and this will be clear in the graphs I produce. I have now simplified my results so that I can easily plot my graph from these results. I have made them show the stress to the power of 10 to the 7, and strain which is ten to the power of minus three. Here are my two tables: Results for constantan (for graph) Stress Nm times 10 Strain Youngs Modulus times by 10 (times 10 )   Stress Nm times ten Strain (e/L) Youngs Modulus times by ten times by ten Analysis: In this experiment my aim objective was to find youngs modulus from copper and constantan wire. I have shown this by taking the first step which was to produce the results table, and from this I have plotted the graphs showing the force against the average extension. Observing my graphs you can see that I have plotted two separate graphs showing force against the average extension for both materials. Furthermore, you can also see that I have created the graphs showing stress-strain for copper and constantan. This graph typically shows youngs modulus. The wires had reacted to the weights in the way that I had expected as I predicted that constantan wire will have the higher youngs modulus and is more tough typically because it is an alloy which contains 40% nickel which makes this element extra strong, whereas the copper is a pure metal and will not be able to take the strain of the load and this is proven as the copper wire could only take 24N as it broke, whereas constantan wire could take almost double the amount 42N. This illustrates that constantan wire needs more force to extend the wire; whereas copper is a material which is frail and would extend by a suitable weight which puts strain onto the material. We can perceive that copper is more easy to stretch by the information I have produced in the table as at 20N it had an average extension of 0. 013 metres, however constantan wire if what my theory is, then I believe that at 20N, constantan should have a smaller average extension then copper has. Looking at the table, the average extension for constantan at 20N is 0. 006 metres. This proves my theory correct as these two results show the difference between the two materials instantly. We can now say that constantan is more tensile, as an alloy it has an enables the dislocation of the atoms which help grip the structure together and therefore give it the property of being tough, this is explained in my diagram I have drawn on page 3. I believe that the atoms in the pure metal copper, had displaced and therefore become unstable when the load was placing strain upon the wire. This would ultimately, make the atoms move out of position and break up, resulting in the wire shattering. This is why when the copper wire had reached its maximum load which was 24N, the atoms had suffered a permanent deformation in the arrangement as they would have been changed in their formation, but unable to move back. This is the same principle with the wire, as it was being stretched and the atoms moved out of place, but the load was greater then the elastic limit could handle and this is why there is a permanent deformation where the wire does not return back to it original shape and changes length, resulting in the increase in extension. In the constantan wire, this would be identical however the atoms would be harder to move out of place, as this material can handle far more load then the copper wire could. So at the same weight (24N) this wire would still return to its original shape because it is in its elastic state. However once it exceeds it elastic limit, then the wire loses its formation of atoms and does not return to its original shape. Here is a graph showing elastic and plastic locations in this graph, this is a way of working out youngs modulus, or by working out the gradient of a graph. I have also found a diagram from my physics textbook, which shows the general yield stress for materials including copper and constantan. By observing the diagram this will give further evidence for my analysis upon the results I have achieved: What each of my graphs show:   My first graph shows force against the average extension for the copper wire, this graph shows that the average extension had increased with the force, however only to a certain point, as this remained elastic from 0N to 24N. After this remained plastic, where the wire could not handle any more load and had shattered. My second graph shows force against average extension for constantan wire. This wire indicated through the graph actually can handle much load, and it has a very large elastic region, as this alloy is very tough, therefore can handle large amounts of weights. This wire could handle 42N however after it then remains plastic, and broke.   The third and final graph illustrates further insight into the youngs modulus of copper and constantan wire, as I have plotted the two materials on the same graph. It is indicated that constantan has a higher youngs modulus compared to copper material. This is because copper can easily be shattered as it stretched very much compared to constantan. The gradient is smaller compared the constantans, which means copper has the smaller youngs modulus because it is a metal and nothing stronger whereas the constant material has elements such as nickel which gives it the strength it requires to dominate copper. Evaluation: I perceive that this experiment was completed under fair conditions as this was kept a fair test at all times. I believe that repeating the experiment three times, had made this fair and given the accuracy which was needed. I had made sure that the materials were used to 2. 1 metres in length and had the same diameter. However, the errors which appeared in this experiment (uncertainties) are where when measuring the wire of the constantan or copper I had rounded up or down the value depending n whether it was greater then X. 5 or below. In my graphs, this is shown as these have been drawn in for average extension, so there is an uncertainty error of about 0.5mm. Another uncertainty spotted I believe is where I had calculated youngs modulus on the graph, I plotted a line of best fit. The line of best fit was drawn in hand by me, however this line can cause uncertainty as this is based on human error and accuracy as everyone will have their own judgment and perception when drawing the line of best fit. Furthermore, I can see that my line of best fit is not totally wrong as looking at the young modulus of copper which is 3*10 to the power of 10, and constantan 6. 40 to the power of 10. We can see that constantan youngs modulus was said to roughly double coppers youngs modulus value, and this is proven by these two figures given. We can see that these two figures are nearly double in difference therefore they seem to be correct. When measuring the wire with a metre stick I found there were an uncertainty of 0. 5mm, and an uncertainty of 1% with the weights. The experiment in general had gone according to plan. Im pleased with what I had found out through the results as I believe my prediction was correct and backed up by the results from the graph I had achieved. I believe that repeating the experiment three times meant that I had accurate results as from the average extension I plotted the graphs. Concluding this experiment I had found out that constant had the higher youngs modulus due to it being an alloy and containing the 40% of Nickel which gives it the strength property. Copper however, had been more flexible being a pure metal the atoms were easily dislocated and this resulted in copper breaking very easily as it had a small elastic limit. Improvements-IF TO DO IT AGAIN. Bibliography:I had obtained information from the following resources: o AS physics textbook: I had found this source extremely interesting and useful as much of the diagrams I had used came from this textbook, which explained the comparison between the pure metal and alloy. This textbook had given much information which was relevant to this coursework. 8/10 o AS physics CD-ROM: I had achieved the diagrams mostly from the CD ROM, this CD had many diagrams which were useful, however this did not contain much written information which was useful and could aid me with this coursework.6/10 o Internet: I found that the information from these sources seemed very reliable and information I had gained, helped me understand the complex issues with the relation of physics to youngs modulus. I had obtained the various information I have included on the background information on the sensor from the following Internet sites: o http://www. emsl. com/tensile_strength. html o http://www. encyclopedia. com/html/Y/Youngsmo. asp o http://hyperphysics. phy-astr. gsu. edu/hbase/permot3. html.

Its Time to Put an End to Child Labor Essay example -- Argumentative

It's Time to Put an End to Child Labor People believe that child labor does not affect them, not realizing that the Persian rugs they put their feet on are made by suffering children in a dark, small room. They don’t realize the soccer balls that their children are kicking around outside are made by children themselves, who slave away for little or no pay at all. In 1999, ap-proximately 250 million children are employed or enslaved across the world for little or no money at all (Gay 23). Imagine how these child workers are depraved from experi-ences the joys of childhood. These poor children never get to play outside or enjoy a simple game. Child labor is a harrowing experience for anyone involved in it. In order to end this travesty of child labor, the world must unite as one to create coalitions and companies that aid child laborers. All over the world children are laboring for little or no money. Desperate families sell their children in order to get a loan from corrupt employers. The child is treated like a slave; he has no say in the matter and can be forced to work up to 18 hours a day, seven days a week (Barry 1). The conditions of these children are of great public concern. U.S. Secretary of Labor Robert Reich and other notable politicians attempt to end the suf-fering of these impoverish children. Several companies and organizations are also con-cerned with the squalor these workers live in and their staggering working conditions. They attempt to not purchase products made by child laborers (Boukhari 2). Children all over the world are suffering from physical, emotional, and sexual abuse that transpires from ch ild labor. Physical abuse is common place in sweatshops where children work. If the child becomes too slow, or makes a mistake or whines, the child could be beaten, tortured, or slaughtered (George 35). Small children are forced to climb under dangerous working machines and handle hazardous items with bare hands. But even worse is the sexual abuse of children. The unscrupulous employers often pur-sue children as sexual prey, raping boys and girls everyday. Children are forced to live in brothels and have sex with men up to six times their own ages (Boukhari 4). Many of the carpet factories serve as enlistment centers for brothels. The only money these girls make is usually less than 15-cent tips from clients (Berry 2). Even after the chi... ...d by the dire effects that will come. In order to stop the decadent policy of child labor, the world must work as one and create coalitions and companies. An example of a company that is attempting to put an end to child labor is the Rugmark Corporation. The Rugmark Corporation makes highly profitable rugs that are promised to be child labor free. The Foulball campaign seeks to eliminate the use of child labor in the manufacture of soccer balls. The Foulball campaign generated almost immediate publicity, thousands of soccer players from both the United States and Europe requested that child labor was to be eliminated from soccer ball manufacturing. The Foulball campaign hopes to spread this practice to other balls such as baseballs, footballs, and basketballs. Another company that works against child labor is UNICEF. UNICEF works to protect children all over the world. It raises money to save destitute children. But we need more campaigns to end child labor. We must force other countries to abide by international law. The only way to stop this problem is to unite as one and perform together. Child labor is a horrible affair that must b e stopped for the good of the entire world.

Marketing to the Bottom of the Pyramid

The concept of the Bottom of the Pyramid (BOP) market was originally developed by C.K. Prahalad in â€Å"The Fortune at the Bottom of the Pyramid† to highlight a large potential market made up of a large segment of the world’s population that has, until recently, been an ignored market segment among multinational companies. In an age of increasing global competition and near-saturation for some products in more mature markets, this multi-cultural segment, made up of people from all parts of the world that earn less than two dollars a day, can generate significant revenues and be profitable for companies who have developed appropriate strategies for reaching this market segment. Among the issues related to BOPMs are establishing appropriate distribution channels, developing and pricing products that have value for those in these markets, and finding creative ways for financing. In terms of financing, this would include not only that related to the purchase of a product for those with relatively low incomes, but would also include strategies for financing business initiatives on the local level. Perspectives Stakeholder would include the local populations that make up the BOPMs. Cultural considerations must be a key component of product development and advertising. Care must be given that products will not harm those to whom they are marketed. Also, companies are stakeholders in that new strategies including BOPMs may be important ways for a company to grow organically. In extension, many large multinational firms are public-traded companies. As such, shareholders are the owners and increasing shareholder value is a goal. Discussion †¢ Ethics of marketing certain products to people in the BOPM. †¢ Issues related to distribution channels. It seems that companies marketing to BOPMs must think beyond the traditionally accepted distribution channels. Many people in BOPMs live in remote, harder to reach, areas. †¢ Issues related to advertising. Television and radio advertising are one approach, but may not be the best way to reach the target market. Action/Recommendation Distributions Channels A successful strategy for marketing to these segments would include more direct marketing, with people getting paid on commissions. For retailers, marketing efforts should be geared toward lower volume sales in smaller stores. In contrast to what we are accustomed to in our domestic market in which we shop in large retails stores where the prices per unit decreases as the product size increases, BOPMs would require a different approach. These markets would require smaller, possibly individual-size products that could be purchased for a relatively small amount of money for people that probably do not have credit and do not have a significant amount of money on any given day. Product Development In addition to the size of products offered, other important factors need to be considered. In terms of packaging, climate is important—products may be offered in small, more or less open-air stores in hot climates, for example. More important for products that have a technical component, consideration also needs to be given to the level of features available. Whereas some features ,such as battery capacity—important as noted in the case for those without reliable sources of electricity—may be critical for product success, others may not be useful and my unnecessarily increase the price or the complexity of the product.

Enduring Physical and Mental Abuse in Incidents in the...

â€Å"Cruelty is contagious in uncivilized communities.† In Incidents in the Life of a Slave Girl, Harriet Jacobs provides a portrayal of her life as a black slave girl in the 1800s. Though Harriet described herself as having yellowish brown skin; she was the child of a black mother and a white father. â€Å"I was born a slave; but I never knew it till six years of happy childhood had passed away.† Born with one drop of black blood, regardless of the status of her white father, she inherited the classification of black and was inevitably a slave. Harriet endured years of physical and mental abuse from her master and witnessed firsthand how slaves were treated based on the color of their skin. Years of abuse can only be taken for so long, like many†¦show more content†¦Instead of receiving reasonable interest rates or regular loans, they were redirected to apply for subprime loans. Why would the brokers do this? Ironically, there are no laws against a mortgag e broker asking a borrower’s race, or a borrower refusing to select race identity on a loan application. As a matter of fact, if a borrower refuses to select their ethnicity on an application; brokers are inclined to guess the borrower’s race to be in compliance with the Home Mortgage Disclosure Act. This is a requirement to ensure mortgage lenders are not discriminating based on race. Hence, mortgage lenders have the right to guess a borrower’s race based on the physical color of skin. In America’s judicial system, the color of skin or race are often equated with criminal behavior. Dr. King once said â€Å"I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin, but by the content of their character.† As United States citizens, we are not convicted of a crime until proven guilty. However, racial profiling aids law enforcement on deciding when to pursue or detain a suspect based on race. This method undoubtedly categorizes that certain races are more prone to commit crimes. Nevertheless, racial profiling is a violation of constitutional rights thus protected by federal law; oddly it is often disregarded by states.Show MoreRelatedIncidents in the Life of a Slave Girl1112 Words   |  4 Pages In the non-fiction book â€Å"Incidents in the Life of a Slave Girl,† by Harriet A. Jacobs and published in Boston in 1861. The author Jacobs was born into slavery in 1813, in a town called Edenton, North Carolina. Jacob uses the pseudonym Linda Brent to narrate her first person account. The book opens with Jacobs stating her reasons for writing a biography of her life story. Her story is agonizing and she had rather have kept it confidential, although she felt that by making it public thatRead MoreDeveloping Management Skills404131 Words   |  1617 PagesStress-Reduction Techniques 144 SKILL ANALYSIS 147 Cases Involving Stress Management 147 The Turn of the Tide 147 The Case of the Missing Time 150 SKILL PRACTICE 155 Exercises for Long-Term and Short-Run Stress Management The Small-Wins Strategy 155 Life-Balance Analysis 156 Deep Relaxation 158 Monitoring and Managing Time 159 SKILL APPLICATION 161 Activities for Managing Stress 161 Suggested Assignments 161 Ap plication Plan and Evaluation 162 SCORING KEYS AND COMPARISON DATA Stress Management AssessmentRead MoreLibrary Management204752 Words   |  820 Pageslu.com Printed in the United States of America The paper used in this book complies with the Permanent Paper Standard issued by the National Information Standards Organization (Z39.48-1984). 10 9 8 7 6 5 4 3 2 1 To our grandchildren Annika, Jacob, Katherine, Madison, Magnus, and Molly Contents Illustrations . . . . . Preface . . . . . . . . . Acknowledgments . The Web Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Read MoreManagement Course: Mba−10 General Management215330 Words   |  862 PagesChange 2. Images of Managing Change 121 121 147 147 Text 3. Why Organizations Change Text Cohen †¢ Effective Behavior in Organizations, Seventh Edition 14. Initiating Change 174 174 Text iii Cases 221 221 225 The Consolidated Life Case: Caught Between Corporate Cultures Who’s in Charge? (The)(Jim)(Davis)(Case) Morin−Jarrell †¢ Driving Shareholder Value I. Valuation 229 229 253 279 1. The Value−Based Management Framework: An Overview 2. Why Value Value? 4. The Value Manager