Descent of a parachute Essay Example for Free

Descent of a parachute Essay How the surface area affects the rate of descent. Surface area of parachute (cmi ) Mass of parachute. (g) Time taken to descend (s) Height dropped from (m) Average speed (m/s) 10 5. 5 1. 11 2 1. 80 How the mass of the parachutist affects the rate of descent Mass of parachute. (g) Surface area of parachute (cm) Time taken to descend. (s) Height dropped from (m) Average speed (m/s) 10. 2 20 1. 66 2 1. 20 The preliminary experiment provided some useful results, which will help me to use better measurements in the main experiment. The measurements of area in the first worked well. The material used in the preliminary experiment was too rigid and did not travel smoothly through the air. For my main experiment I have decided to use bin bags which flow through the air more easily. The mass was appropriate for the size of the parachute. All other factors seemed to work well within the experiment. The main experiment will consist of 6 examples rather than three to produce a better range of results. The range of values are very important when doing an experiment i. e. they should not be too big or too small. I feel that range of numbers I have chosen work very well after having done the preliminary experiment and seeing them in action. Safety Safety is always an important feature when it comes to executing an experiment even more so when objects are being dropped from a high height. To ensure the highest level of the safety the following issues need to be taken into account;   No one should be underneath where the object is being dropped   Care must be taken when standing on chairs   Running can cause serious accidents.   Do not leave scissors around as they are sharp and can hurt people. No rubbish should be left on the floor to prevent people tripping up. RESULTS Tables of results How the surface area affects the rate of descent Surface area of Parachute (cmi ) Mass of parachute (g) Time (s) Height (m) Average Speed ( m/si ) 10   How the mass affects the rate of descent Mass of parachute(g) Surface area of Parachute (cmi ) Time (s) Height (m) Average Speed ( m/si ). ANALYSIS Experiment 1 The first experiment looked at how the surface area of a parachute affected its rate of descent. I found out that the larger the surface area, the slower the average rate of descent. The theory behind these results which was discussed in the hypothesis is that when any object falls, it almost always encounters some degree of air resistance. Air resistance is the collisions of air particles with the surface area (facing the floor) whilst falling through the air. The larger the surface area the more collisions there will be. Air resistance slows falling objects downwards as I found out, when doing the experiment. The larger the surface area of the parachute was, the lower the average rate of decent. Below is a diagram, which shows how air resistance affects the fall of an object (a parachute in this case). Graph The results that I obtained supported my prediction. I predicted the larger the surface area, the slower the rate of descent and by looking at the graph and table these results are shown. I thought that there would have been a bigger difference between the speeds but the differences between the sizes of parachutes were obviously too small. The bigger the surface area, the more air resistance so therefore it takes a shorter time to reach terminal velocity (the downward and upward force balance each other meaning there is no acceleration). The object does not have to increase to such large speeds as to balance out the forces so it stops accelerating in a shorter amount of time meaning it takes longer to fall. The results produce quite a smooth curve, which did not require a line of best fit. This shows us that the measurements were applied accurately and the experiment was performed efficiently with equitable results. Experiment 2 This experiment was looking at how the mass of a parachutist and its parachute affects the rate of descent. From my results I found out that the bigger the mass of the parachute, the faster the average rate of descent. The amount of air resistance depends on the speed of the falling object. Objects will continue to accelerate to higher speeds until they encounter an amount of air resistance, which is equal to their weight. A parachutist with a bigger mass experience a greater force of gravity due to their larger mass (f = 10m) than a parachutist with a smaller mass. A parachute will therefore accelerate to a higher speed before reaching a terminal velocity. The more massive the object the higher its speed will be until it encounters terminal velocity. Therefore, more massive objects fall faster than less massive objects because they are acted upon by a larger force of gravity. For this reason they accelerate to higher speeds until the air resistance equals the force of gravity This experiment has demonstrated the theory that the more massive an object, the faster it will fall when encountering air resistance. My prediction supported the results as each time I increased the mass of the parachute, the faster the average speed was. Below is a diagram which demonstrates this theory. Graph This graph shows the results of the experiment. This graph did require a line of best fit which shows that the results were not so regular and perhaps were not so accurate. They did show though that the bigger the mass, the faster the rate of descent. The gradient was quite gentle which shows that the speed increased gently. EVALUATION The procedure seemed to be accurate and to have gone well and produced some results, which backed up the hypothesis. To try and make the experiment as accurate as possible, I measured the time taken to descend three times and then found an average. To show the calculations for the average speed, I should have written down the different results for the time taken to descend. This would support the figure for the average speed, as it would show that I performed the experiment three times for each different weight or surface area depending on the experiment. I got various different people to time the descent as each person has a different reaction time which in investigations where the measurements are so small it is important that I use different people as a split second can make a big difference. There were no results, which were peculiar or stood out in either experiment. The procedure was suitable for the aim, which I had to complete. I felt that the scientific evidence that I collected at the beginning created a strong basis on which to stand. My conclusion was firm as I was very sure of the theory behind this investigation after having read up about it and seeing it happen in every day life situations. The evidence which I accumulated was reliable as I had made sure that I could attempt to make everything as accurate as possible. I used a variety of seven measurements, which I felt was enough and as I have seen by the results seemed to work well. As there were no strange results, which seemed out of place I can see that the results were reliable. They were also constant, which backs up, the fact that the results were reliable. Although the experiment went well there are various changes, which I can make to get even more accurate results.   Use even more measurements, as this will provide more results.   Do each measurement five times instead of three to get a more accurate measurement.   Make the structure of the parachute better and not so messy. Drop the parachutes from a higher height to get a bigger measurement as this will mean that the reaction time of the person dropping the parachute will make a smaller difference. Use a bigger difference of measurements. Take more care to find a material, which flows through the air well.   Use the stopwatch as accurately as possible.   Do more examples in the preliminary experiment. Whilst doing the experiment I tried to do as many things to ensure an accurate result but the problem was time. I felt it was rushed so I did not have as much time as I would have liked. The results did seem to be accurate and were constant which shows that the investigation was not too inaccurate and worked well.

Abraham Lincoln as a Dangerous Speaker Essay -- Presidents essays rese

  Ã‚  Ã‚  Ã‚  Ã‚  Many people remember President Abraham Lincoln as being a very gifted orator as well as a dignified leader of our country. Through his many speeches and writings, Abraham Lincoln captivated American minds and gained millions of followers. In Lincoln's "Perpetuation speech," given before the Young Men's Lyceum of Springfield, Illinois, in 1838, Lincoln himself stated that our country was in great danger. He speaks of people such as Alexander the Great, Julius Caesar and Napoleon and then asks, "Is it unreasonable to expect , that some man possessed of the loftiest genius, coupled with ambition sufficient to push it to its utmost stretch, will at some time, spring up among us?" (Grafton, page 7). In this, he shares his fear that some man with great ambition and power could exist in this country who is not satisfied with just the power of the presidency and strive for more than that. I believe that Lincoln had the power to be one of those people. When Lincoln's orati ons and writings are carefully analyzed, one can see how he used his wit and intelligence to manipulate the American people. With his intelligence and immense popularity, Lincoln could have easily been one of the men that he spoke of. He used his gift as an orator to get ahead and that, I believe, made him a threat to American society.   Ã‚  Ã‚  Ã‚  Ã‚  Abraham Lincoln was a very popular man among the American people. He was there for the country through the Civil War, whether good or bad times. In the North he was the great emancipationist. Lincoln was loved by many, and he could have used this to his advantage. One reason that he was so loved was because he had the ability to draw people's attention with his speeches. After his assassination and the reaction of the American people, the fact that he was so loved was a surprise to some people in Washington. There was a three week funeral procession where Lincoln's body was taken to the big cities by a special train so that the people could mourn him. "Democrat Charles Mason of Iowa thought the whole affair a political trick, like the 'crafty skill of Mark Antony in displaying to the Roman people the bloody mantle of Caesar'," (Donald, page 5). This analogy was made as an argument between political parties, but I think that it just shows how important Lincoln real ly was, being compared to the great Julius Caesar. It is widely believed that popular Preside... ...vement is wrong. Lincoln, however, when giving this speech doesn't come right out and say that he believes that they are wrong. In this way he gains more supporters by befriending them and not telling them straight out that they are wrong. At that point in time, Lincoln needed those votes. However, he got them by dishonest means. That really doesn't sound like the "Honest Abe" that all of the people knew and trusted.   Ã‚  Ã‚  Ã‚  Ã‚  I believe that President Abraham Lincoln was a man with a lot of power. Lincoln was a very dangerous speaker. He could have easily used this power and his ability as an orator to become one of those men that are not satisfied with just the presidency and could have tried to have more. I believe that for this reason, Lincoln was a threat to our society. However, the people did not realize this because he had them so entranced by his wonderful speeches and writings. At a normal glance, it looks as if there is nothing hidden in those speeches. When they are looked at a little more closely though, one can see how Lincoln used his immense talent to trick the people into supporting him. Through his beautifully crafted orations, Abraham Lincoln gained many followers.

PetSmart, Inc Essay

PetSmart, Inc. is the largest specialty retailer of services and solutions for the lifetime needs of pets with more than 885 pet stores in the United States and Canada. It supplies a broad range of pet food and pet supplies that are competitively priced. Many of its stores have in-store cat and dog boarding facilities called as pet hotels. PetSmart provides online pet supplies and pet care information, pet training, pet grooming and pet adoption services. The web site of PetSmart is fairly well developed and communicates a good amount of online information to its visitor with links to specific pets like dogs, cats, fish etc. It also provides a link that will help the visitor to locate the store closest to him. The website has an excellent link called petsmartcharities through which PetSmart is able to clearly communicate its social initiatives of saving and providing a lifelong loving home for every homeless pet. It is also very successful in communicating how the visitor can participate in their social initiatives through the purchase of flowers, collectible dog or cat ornaments and wrapping paper and also silver logo charms as gift for pet-loving friends or family members. The mission or the very purpose of the existence of the company that is ‘providing a lifelong loving home for every pet’ is not clearly communicated to the website visitor and can be identified only if the visitor is looking for it. The website is also ineffective in delivering the message with respect to the ethical values and practices of the company in conducting its business. This is a very critical message in today’s business environment for all the stakeholders of the company, specially the informed investors and the customers. A company’s website is a powerful tool for communicating vital information to the concerned. The company should include a clear mission and vision statement at the very beginning on the webpage ‘about us’. A separate link communicating about its core business values, ethical practices and an ethical code of conduct as followed by the company should also be provided.

What Is Popular Sovereignty

The popular sovereignty principle is one of the underlying ideas of the United States Constitution, and it argues that the source of governmental power (sovereignty) lies with the people (popular). This tenet is based on the concept of the social contract, the idea that government should be for the benefit of its citizens. If the government is not protecting the people, says the Declaration of Independence, it should be dissolved. That idea evolved through the writings of Enlightenment philosophers from England—Thomas Hobbes (1588–1679) and John Locke (1632–1704)—and from Switzerland—Jean Jacques Rousseau (1712–1778). Hobbes: Human Life in a State of Nature Thomas Hobbes wrote The Leviathan in 1651, during the English Civil War, and in it, he laid out the first basis of popular sovereignty. According to his theory, human beings were selfish and if left alone, in what he called a state of nature, human life would be nasty, brutish, and short. Therefore, to survive people give over their rights to a ruler who provides them with protection. In Hobbes opinion, an absolute monarchy provided the best form of security. Locke: The Social Contract Limiting Rulers Powers John Locke wrote Two Treatises on Government in 1689, in response to another paper (Robert Filmers Patriarcha) which argued that kings have a divine right to rule. Locke said that the power of a king or government doesnt come from God, but comes from the people. People make a social contract with their government, trading away some of their rights to the ruler in exchange for security and laws. In addition, Locke said, individuals have natural rights including the right to hold property. The government does not have the right to take this away without their consent. Significantly, if a king or ruler breaks the terms of the contract—by taking away rights or taking away property without an individuals consent—it is the right of the people to offer resistance and, if necessary, depose him.   Rousseau: Who Makes the Laws? Jean Jacques Rousseau wrote The Social Contract  in 1762. In this, he proposes that  Man is born free, but everywhere he is in chains. These chains are not natural, says Rousseau, but they come about through the right of the strongest, the unequal nature of power and control. According to Rousseau, people must willingly give legitimate authority to the government through a social contract for mutual preservation. The collective group of citizens who have come together must make the laws, while their chosen government ensures their daily implementation. In this way, the people as a sovereign group look out for the common welfare as opposed to the selfish needs of each individual.   Popular Sovereignty and the US Government The idea of popular sovereignty was still evolving when the founding fathers were writing the US Constitution during the Constitutional Convention of 1787. In fact, popular sovereignty is one of six foundational principles on which the convention built the US Constitution. The other five principles are a limited government, the separation of powers, a system of checks and balances, the need for judicial review, and federalism, the need for a strong central government. Each tenet gives the Constitution a basis for authority and legitimacy that it uses even today. Popular sovereignty was often cited before the US Civil War as a reason why individuals in a newly organized territory should have the right to decide whether or not slavery should be allowed. The Kansas-Nebraska Act of 1854 was based on the idea—that people have a right to property in the form of slaves. It set the stage for a situation that became known as Bleeding Kansas, and it is a painful irony because certainly Locke and Rousseau would not agree that people are ever considered property. As Rousseau wrote in The Social Contract: From whatever aspect we regard the question, the right of slavery is null and void, not only as being illegitimate, but also because it is absurd and meaningless. The words slave and right contradict each other, and are mutually exclusive. Sources and Further Reading Deneys-Tunney, Anne. Rousseau shows us that there is a way to break the chains—from within. The Guardian, July 15, 2012.  Douglass, Robin. Fugitive Rousseau: Slavery, Primitivism, and Political Freedom. Contemporary Political Theory 14.2 (2015): e220–e23.Habermas, Jurgen. Popular sovereignty as procedure. Eds., Bohman, James, and William Rehg. Deliberative Democracy: Essays on Reason and Politics. Cambridge, MA: MIT Press, 1997. 35–66.Hobbes, Thomas. The Leviathan, or the Matter, Forme, Power of a Common-Wealth Ecclesiasticall and Civill. London: Andrew Crooke, 1651. McMaster University Archive of the History of Economic Thought. Hamilton, ON: McMaster University.  Locke, John. Two Treastises of Government. London: Thomas Tegg, 1823. McMaster University Archive of the History of Economic Thought. Hamilton, ON: McMaster University.  Morgan, Edmund S. Inventing the People: The Rise of Popular Sovereignty in England and America. New York, W.W. Norton, 1988.  Reisman, W. Michael. Sovereignty and Human Rights in Contemporary International Law. American Journal of International Law 84.4 (1990): 866–76. Print.Rousseau, Jean-Jacques. The Social Contract. Trans. Bennett, Jonathan. Early Modern Texts, 2017.