Simple Pendulum Lab

The Simple Pendulum Objective and Background Objective: The Objective of this experiment is to examine the simple harmonic motion and to determine the value of the acceleration due to gravity from the analysis of the period of the simple pendulum. [1] Background: There are three equations that will be used to calculate the period of motion of the simple pendulum. They are the slope of the line of the graph of T? against L, and the gravity of the pendulum motion.The period of the motion is the time needed for one complete cycle that a pendulum bob swing from the initial position to the other end, and then back to the initial position. [1] The equation to calculate period is, T = 2? Lg Where, T = Period of the motion, measured in s. L = Length of the pendulum, measured in cm. g = Acceleration due to gravity, measured in m/s2. The slope of the line in the graph of T? against L can be used to determine the gravity of the pendulum motion. It is because, y = mx m = T? L= 4 g = Slope of the line in the graph T? /L. Therefore, to find the gravity of the pendulum motion, we can use the slope of the graph.The slope of the graph is given by the formula, g = 4 m g = Acceleration due to gravity, measured in m/s?. Procedure and Observations Materials: * String * Metre Stick * Stop watch * Stand * Pendulum bob Procedure: 1) Materials listed above were taken for the experiment. 2) The pendulum bob was tied tightly with the string. 3) The string with the pendulum bob was hung on the stand. ) A meter stick was used to measure the distance between the centre of mass of the bob and the top of the string. 5) The distance was recorded in the observation table. 6) The pendulum ball was held at a distance from the centre and it was released. 8) A stop watch was used to time the time needed to complete ten cycles. 9) The time was recorded in the observation table. 10) Steps 4-7 were repeated four more times with different lengths. Observations: L (m)| 10T (s)| 0. 185| 9. 01| 0. 39| 14. 13| 0. 595| 15. 04| 0. 79| 17. 58| 1| 19. 67|Diagram of the Pendulum Figure [ 1 ] Calculations and Results Method 1 – Graph of T2 vs. L Data collected L(m)| T2(s2)| 0. 18| 0. 81| 0. 39| 1. 99| 0. 59| 2. 37| 0. 79| 3. 09| 1| 3. 86| Hand drawn graph ?x ?y Figure [ 2 ] The slope can be determined by m=? x? y. So, by taking a value for x x = 0. 4 cm y must then be y = 1. 4 cm m= 1. 4 cm0. 4 cm m=3. 5 The error would be given by ?mm= ? x1x12+ ? x2x22 ?m= m 0. 051. 42+ 0. 050. 42 ?m= 3. 5 0. 051. 42+ 0. 050. 42 ?m=0. 45 The acceleration due to gravity is given by g=4? 2m g=4? 23. 5 g=4? 23. 5 g=11. m/s2 Calculating the error for g would yield ?gg= ? mm2 ?g= g 0. 453. 52 ?g= 11. 30. 453. 52 ?g= 1. 45 m/s2 g=11. 3 m/s2 Â ± 1. 45 m/s2 Solving for the percentage deviation would give % deviation= Actual value-Expected valueExpected value* 100% Expected value=9. 8 m/s2 % deviation= 11. 3 m/s2-9. 8 m/s29. 8 m/s2*100% % deviation= 11. 3 m/s2-9. 8 m/s29. 8 m/s2*100% % deviation= 15. 3% Me thod 2 – Linear Regression Excel graph Figure [ 3 ]The equation of the line is given by T2 = 3. 53L + 0. 33 Where m=3. 53 The acceleration due to gravity is given by =4? 2m g=4? 23. 53 g=4? 23. 53 g=11. 1 m/s2 Solving for the percentage deviation would give % deviation= Actual value-Expected valueExpected value* 100% Expected value=9. 8 m/s2 % deviation= 11. 1 m/s2-9. 8 m/s29. 8 m/s2*100% % deviation= 11. 1 m/s2-9. 8 m/s29. 8 m/s2*100% % deviation= 13. 2% Conclusion By comparing these two methods of calculating the acceleration due to gravity it is clearly noticeable that there is a difference between the two, when it comes to the accuracy. When calculating g using the hand drawn graph method it yielded =11. m/s2 Â ± 1. 45 m/s2. However, when using the linear regression method on excel, it yielded g=11. 1 m/s2. This is clearly closer to the expected value of 9. 8 m/s2. There are several reasons contributing to the conclusion that linear regression is more accurate, than meas uring calculating the slope off of a hand drawn graph. First of all, computers are much more accurate than humans. There is no denying the fact that humans are not perfect and no hand drawn graph will be as precise as a computer drawn graph.A ruler was being used, which may lead to believe that the line is perfectly straight, whereas it is actually not. This is clearly noticeable when one zooms in on a hand drawn graph. Another problem with the ruler is that no matter how hard one tries to measure the distance between two different points, one will never be able to get the exact distance. Computers however, Excel in this case, draw perfectly straight lines. Also the location of line of best fit line, in the hand drawn part of the experiment, was estimated, which obviously leads to an inaccurate result.Excel however, uses the calculation of linear regression to draw the line of best fit and this is extremely accurate, since the exact slope is being calculated by Excel. It is clear th at the method of linear regression is more accurate by looking at the percentage deviations for each method. The % deviation for the hand drawn graph yielded 15. 3%, whereas the percentage deviation for the linear regression method only was 13. 2% Even though the linear regression method was more accurate than the hand drawn method, there was still a pretty significant difference, between that value, namely g=11. m/s2, and the expected value of 9. 8 m/s2. This is due to a few sources of error when this experiment was conducted. One of the errors that contributed to this difference was that the length of the string was not exactly measured. Thus, the relation between the length and the period was wrong, leading to false results. Another reason that contributed to the inaccuracy was the fact that when the bob was not swinging the way it was supposed to. It was only supposed to have a linear motion, but it had a slight circular motion, which of course lead to a longer period.This again resulted in a wrong relation between the period and the length, leading to a wrong result. There was another major aspect to the experiment that lead to this result. Namely the fact one could not tell where the bob actually started its swinging motion exactly; therefore the exact period could not be measured with the stopwatch. It is evident however, that if these errors could have been avoided, the acceleration due to gravity could have been calculated very accurately using the method of linear regression. References [1] PCS 125 Laboratory Manual, 2008

Free Essays on Causes Of The American Civil War

The South, which was known as the Confederate States of America, seceded from the North, which was also known as the Union, for many different reasons. The reason they wanted to succeed was because there was four decades of great sectional conflict between the two. Between the North and South there were deep economic, social, and political differences. The South wanted to become an independent nation. There were many reasons why the South wanted to succeed but the main reason had to do with the North’s view on slavery. All of this was basically a different interpretation of the United States Constitution on both sides. In the end all of these disagreements on both sides led to the Civil War, in which the North won. There were a few reasons other then the slavery issue, that the South disagreed on and that persuaded them to succeed from the Union. Basically the North favored a loose interpretation of the United States Constitution. They wanted to grant the federal government increased powers. The South wanted to reserve all undefined powers to the individual states. The North also wanted internal improvements sponsored by the federal government. This was more roads, railroads, and canals. The South, on the other hand, did not want these projects to be done at all. Also the North wanted to develop a tariff. With a high tariff, it protected the Northern manufacturer. It was bad for the South because a high tariff would not let the south trade its cotton for foreign goods. The North also wanted a good banking and currency system and federal subsidies for shipping and internal improvements. The South felt these were discriminatory and that they favored Northern commercial interests. Now the main reason for the South’s secession was the Slavery issue. Basically the South wanted and needed it and the North did not want it at all. The South was going to do anything they co... Free Essays on Causes Of The American Civil War Free Essays on Causes Of The American Civil War The South, which was known as the Confederate States of America, seceded from the North, which was also known as the Union, for many different reasons. The reason they wanted to succeed was because there was four decades of great sectional conflict between the two. Between the North and South there were deep economic, social, and political differences. The South wanted to become an independent nation. There were many reasons why the South wanted to succeed but the main reason had to do with the North’s view on slavery. All of this was basically a different interpretation of the United States Constitution on both sides. In the end all of these disagreements on both sides led to the Civil War, in which the North won. There were a few reasons other then the slavery issue, that the South disagreed on and that persuaded them to succeed from the Union. Basically the North favored a loose interpretation of the United States Constitution. They wanted to grant the federal government increased powers. The South wanted to reserve all undefined powers to the individual states. The North also wanted internal improvements sponsored by the federal government. This was more roads, railroads, and canals. The South, on the other hand, did not want these projects to be done at all. Also the North wanted to develop a tariff. With a high tariff, it protected the Northern manufacturer. It was bad for the South because a high tariff would not let the south trade its cotton for foreign goods. The North also wanted a good banking and currency system and federal subsidies for shipping and internal improvements. The South felt these were discriminatory and that they favored Northern commercial interests. Now the main reason for the South’s secession was the Slavery issue. Basically the South wanted and needed it and the North did not want it at all. The South was going to do anything they co... Free Essays on Causes Of The American Civil War The South, which was known as the Confederate States of America, seceded from the North, which was also known as the Union, for many different reasons. The reason they wanted to succeed was because there was four decades of great sectional conflict between the two. Between the North and South there were deep economic, social, and political differences. The South wanted to become an independent nation. There were many reasons why the South wanted to succeed but the main reason had to do with the North’s view on slavery. All of this was basically a different interpretation of the United States Constitution on both sides. In the end all of these disagreements on both sides led to the Civil War, in which the North won. There were a few reasons other then the slavery issue, that the South disagreed on and that persuaded them to succeed from the Union. Basically the North favored a loose interpretation of the United States Constitution. They wanted to grant the federal government increased powers. The South wanted to reserve all undefined powers to the individual states. The North also wanted internal improvements sponsored by the federal government. This was more roads, railroads, and canals. The South, on the other hand, did not want these projects to be done at all. Also the North wanted to develop a tariff. With a high tariff, it protected the Northern manufacturer. It was bad for the South because a high tariff would not let the south trade its cotton for foreign goods. The North also wanted a good banking and currency system and federal subsidies for shipping and internal improvements. The South felt these were discriminatory and that they favored Northern commercial interests. Now the main reason for the South’s secession was the Slavery issue. Basically the South wanted and needed it and the North did not want it at all. The South was going to do anything they co...

Mendelian Genetics Essay Example

Mendelian Genetics Essay Example Mendelian Genetics Essay Mendelian Genetics Essay Mendelian Genetics * Pea plants have several advantages for genetics. * Pea plants are available in many varieties with distinct heritable features (characters) with different variants (traits). * Another advantage of peas is that Mendel had strict control over which plants mated with which. * Each pea plant has male (stamens) and female (carpal) sexual organs. * In nature, pea plants typically self-fertilize, fertilizing ova with their own sperm. * However, Mendel could also move pollen from one plant o another to cross-pollinate plants. * In a typical breeding experiment, Mendel would cross-pollinate (hybridize) two contrasting, true-breeding pea varieties. * The true-breeding parents are the P generation and their hybrid offspring are the F1 generation. * Mendel would then allow the F1 hybrids to self-pollinate to produce an F2 generation. * It was mainly Mendel’s quantitative analysis of F2 plants that revealed the two fundamental principles of heredity: the law of segrega tion and the law of independent assortment. 2. By the law of segregation, the two alleles for a characters are packaged into separate gametes * If the blending model were correct, the F1 hybrids from a cross between purple-flowered and white-flowered pea plants would have pale purple flowers. * Instead, the F1 hybrids all have purple flowers, just a purple as the purple-flowered parents. * When Mendel allowed the F1 plants to self-fertilize, the F2 generation included both purple-flowered and white-flowered plants. * The white trait, absent in the F1, reappeared in the F2. * Based on a large sample size, Mendel ecorded 705 purple-flowered F2 plants and 224 white-flowered F2 plants from the original cross. Vocab: * Character –heritable feature * Trait – each variant for a character * True-breeding – plants that self-pollinate all offspring are the same variety * Monohybrid cross – a cross that tracks the inheritance of a single character * P generation – (parental) true-breeding * F1- (first fili al) offspring of P generation * F2 – (second filial) offspring from F1 cross * Allele- alternate version of a gene * Dominate allele – expressed in the heterozygote Recessive allele – not expressed in the heterozygote * Homozygote – pair of identical alleles for a character * Homozygous dominant- BB * Homozygous recessive bb * Heterozygote – two different alleles for a character (Bb) * Genotype – genetic makeup * Phenotype – appearance of an organism Law of Segregation the two alleles for each character segregate during gamete production Law of Independent Assortment – Each set of alleles segregates independently Test cross – designed to reveal the genotype of an organism

Scoring Rubric Use and Samples for Elementary Grades

Scoring Rubric Use and Samples for Elementary Grades A scoring rubric evaluates the performance of an assignment. Its an organized way for teachers to assess their students work and learn what areas the student needs to develop in. How to Use a Scoring Rubric To get started you must: First, determine if you are scoring the assignment based on the overall quality and understanding of a concept. If you are, then this is a quick and easy way to score an assignment, because you are looking for an overall understanding rather than specific criteria. Next, read the assignment carefully. Be sure not to look at the rubric just yet because right now you are just focusing on the main concept. Re-read the assignment while focusing on the overall quality and understanding the student portrays. Lastly, use the rubric to determine the final score of the assignment. Learn how to score a rubric and view samples of expository and narrative writing rubrics. Plus: learn how to create a rubric from scratch by using this step-by-step guide to create a rubric. Sample Scoring Rubrics The following basic elementary scoring rubrics provide guidelines to evaluate assignments using the following criteria: 4 - Meaning the students work is Exemplary (Strong). He/she goes beyond what is expected of them to complete the assignment. 3 - Meaning the students work is good (Acceptable). He/she does what is expected of them to complete the assignment. 2 - Meaning the students work is satisfactory (Almost there but acceptable). He/she may or may not complete the assignment with limited understanding. 1 - Meaning the students work is not where it should be (weak). He/she does not complete the assignment and/or has no understanding of what to do. Use the scoring rubrics below as a way to assess your students skills. Scoring Rubric 1 4 Exemplary Student has a complete comprehension of the material Student participated and completed all activities Student completed all assignments in a timely manner and showed perfect performance 3 Good Quality Student has a proficient comprehension of the material Student actively participated in all activities Student completed assignments in a timely manner 2 Satisfactory Student has an average comprehension of the material Student mostly participated in all activities Student completed assignments with help 1 Not There Yet Student does not comprehend the material Students did not participate in activities Students did not complete assignments Scoring Rubric 2 4 The assignment is completed correctly and contains additional and outstanding features 3 The assignment is completed correctly with zero mistakes 2 The assignment is partially correct with no major mistakes 1 The assignment is not completed correctly and contains a lot of mistakes Scoring Rubric 3 Points Description 4 Students understanding of concept if clearly evident Student uses effective strategies to get accurate results Student uses logical thinking to arrive at the conclusion 3 Students understanding of the concept is evident Student uses appropriate strategies to arrive at a result Student shows thinking skills to arrive at the conclusion 2 Student has limited understanding of a concept Student uses strategies that are ineffective Student attempts to show thinking skills 1 Student has a complete lack of understanding of the concept Student makes no attempt to use a strategy Student shows no understanding

Human Biological Science (Pathogens and Disease) Coursework

Human Biological Science (Pathogens and Disease) - Coursework Example Also, in case of a cholera outbreak, cholera cases may be controlled through quarantine as stated under the Commonwealth Quarantine Act 1908. Contacts between infected and non - infected persons should be controlled by monitoring contacts for 5 days from the date of exposure. The environment around cholera victims should be controlled. This can be done through disinfection of clothes and beddings used by cholera patients, and terminal cleaning of the rooms occupied by cholera patients (Department of Health, Victoria, Australia, 2007). The rate at which it grows is dependent on the amount of available nutrients. If nutrients are not available, the fungus enters the log stage. In this stage, it degrades the keratin found in the stratum corneum forming the appropriate amino acids that provide nutrients for reproduction and growth. Once nutrients are available, it enters the stationary stage whereby degradation of keratin slows down. The trichophyton uses its enzymes, proteases in particular to degrade keratin cells and produce nutrients for its survival. To prevent and contain the spread of trichophyton, it is good to ensure that there is enough aeration to the feet, wearing of socks that absorb sweat away from the skin, avoid wearing of wet socks or sharing socks, avoid sharing of towels, drying the feet thoroughly after washing them, washing the feet habitually with water and soap and changing socks and shoes regularly (Department of Biology, Davidson College, 2007). Malaria is transmitted when a female anopheles mosquito takes in the plasmodium gametocytes from an infected person. After 8 – 35 days, the plasmodium develops into its infective form which is transmitted to another individual through a bite of the infected anopheles mosquito. The life cycle is divided into 4 stages that are; growth, development, transmission and reproduction. It is complex as it has varying phases, time length

Drug Testing in the Workplace Essay Example | Topics and Well Written Essays - 1000 words

Drug Testing in the Workplace - Essay Example This approach has streamed a mix though strong reaction with or against the act. The random drug test and medical assistance is legally applicable incase of rational grounds especially when there is probability/occurrence of an accident involving the worker. Observing behavior such as alcoholic odor on breath, glassy eyes, unsteady composure, slurred speech and multiple errors while working substantiate a proper drug test without any prior notification. Incase the test results positive the employee should be granted rehabilitation epoch and permissible to return to employment following an evaluation by a Substance Abuse Professional [SAP] (Drug and Alcohol Testing). Often such an employee challenges the drug test lest if the result is positive. The victim should be elucidated that workplace drug testing is not a vindication of dismissal, it is adapted by the company to safeguard its work environment as well as to achieve the expected performances & production goals by its employees. Strict action maybe taken incase of recurring liabilities of any employee. According to the Merriam-Webster Dictionary, "civil disobedience can be defined as refusal to obey governmental demands or commands especially as a nonviolent and usually collective means of forcing concessions from the government" [1866]. This means that the individuals responsible for civil disobedience are willingly accepting the legal consequences on behalf of their actions since they are involved in falsification of the law. The justification of severity of the legal action is dependant upon the act executed by the persons and its consequences. The mode of action and the motivation for acting must be kept in view while legally examining the act (Civil Disobedience). In terms of environmental causes or animal rights, civil disobedience is often the universal retort by the populace concerned about such issues. Such a dilemma requires action that reflects the protesters' compassion towards the egalitarian principles. The conventional environmental groups have turned believers of incorporating undeviating policies like civil disobedience so as to protect their cause. This usually occurs due to the disappointment concerning the leisurely outcomes of the governmental authorities regarding vindicated environmental issues. It so happens, that such environmentalists involved in safeguarding their root violate the law through their aggressive obliteration of the court, however justified in the other case. These concerns need to be addressed in-depth by the governmental authorities by crafting the laws in accordance to the mainstream causes of today. Ecological laws should be addressed to cater to the environment and the wild life to avoid such extremist behavior of their supporters. From a resource in the Internet find a current article regarding Deep Ecology, environmental activism, or environmental extremism. Read the article and post a short summary (about 100 words or so) of its main points as your response to this DQ. Include the reference information for your article so everyone can find it if they are interested in reading the material. 250 words The

Embracing Diversity Essay Example | Topics and Well Written Essays - 1250 words

Embracing Diversity - Essay Example In order to teach the future generations successfully, the education structure should be thriving in educating all children to interact and communicate with people from diverse backgrounds and with diverse abilities. Early childhood teachers all over the United States should be prepared to educate an increasingly diverse populace of young students. More children from migrant families are taking part in early childhood programs than in the past, and the trend is anticipated to carry on into the next decade. The 2000 population census shows that in only one decade, the number of young students in immigrant households increased by 63%, and not only in large cities, but also in numerous areas of the country. The African American populace both immigrant and nonimmigrant grew at a rate above that of the general populace between 1990 and the new millennium. The Latino population likewise the immigrants and nonimmigrants grew by more than 50% of its original during those same years. The Lati no population is at the moment the single largest cluster contributing to the country’s diversity (Terry & Iriving, 2009). This article concerns the education of children from diverse linguistic and cultural backgrounds who might or might not have disabilities, which need special education services. For culturally, as well as linguistically diverse students (CLD), issues of difference, diversity, and disability can rather be challenging and complex for classroom teachers (Gonzalez, 2011). This paper, with an aim of easing these challenges, will formulate some methods and strategies of achieving the paper’s objective and discuss how the strategies will be assessed. Researchers have referred to the manner culture plays itself out in a classroom set up as a hidden curriculum. The traditional norms which govern classroom communication are mainly rooted in European or American middle-class principles. Regularly there is an inherent anticipation that every student will use t hese customs, even though they are not openly trained in the classroom. Teachers must know that CLD learners also have cultural values and norms, which they also carry into the classroom and might conflict with the educator’s hopes (Gonzalez, 2011). Educators are in the best position to learn about the norms, values and culture of their CLD learners. By having a concern in who the students are, the place they come from, as well as what their worldview is, educators can demonstrate to them that they essentially care about who they are and not only who they can become. Attitudes associated with privilege, status and power can make it tough for some teachers to value diversity among their learners (Ray & Bowman, 2003). For example, students who might be members of a marginalized racial group, economically deprived, or speak English as a secondary language are frequently labeled as vulnerable, poor, disadvantaged or unfortunate. Rather than centering on what learners cannot do, e ducators are encouraged to recognize more regarding their learners’ abilities and strengths (Ray & Bowman, 2003). Nevertheless, centering on what students know needs learning more concerning their traditions and the knowledge, which they take into the classroom. Teachers can then utilize their students’ interests, experiences and background to grow ethnically relevant pedagogy (Terry & Iriving, 2009). Culturally