Air Resistance, Tyres And Friction Essays - Classical Mechanics

Air Resistance, Tyres and Friction Blake Smith Dragsters use a combination of large wide tyres or the rear and small narrow tyres on the front this combination is used for the following reasons: The front wheels: The front wheels are very narrow. This is so a minimum of air resistance or drag affects the dragster with lower drag better acceleration an in turn a better top speed can be achieved all leading to a better pass (race time). Now lets try to understand the concept of air resistance and drag. A basic example is placing your hand out the window with your palm facing forwards as you are driving your car along at about sixty kilometres per hour. You will feel a strong force of the wind (air resistance) pushing back at your hand. Now turn your hand side or so that your little finger is facing the front and your thumb is facing the rear at the same speed. The force of air resistance exerted on your hand is greatly reduced. This force is similar as to that exerted on the front wheels of the dragster. Now dragsters reach speeds of up to five hundred kilometres per hour, imagine the force needed to hold your hand against the wind if your palm was facing the front. It would be much easier to hold your hand side on. The same as it would be much easier for the dragsters engine to push the narrow front wheels compared to large ones. Air resistance is a form of friction (namely fluid friction) a friction from the air, as we know friction is defined as a force that opposes movement. The formula used to determine aerodynamic drag is as follows: Drag = 0.5 * rho * Cd * v2 * S Aerodynamic drag is a function of the following: - rho is the air density, which we cannot change. - v2 is velocity squared which is endeavoured to be maximized for the best time and/or pass. - S is the frontal or cross sectional area which we want to minimize. I.e. less frontal area means that a less significant amount of air resistance impedes the top speed and acceleration. - Cd is the coefficient of drag, which we want to minimize. So the two things with which can be worked with or changed, the frontal area and coefficient of drag, both of which need to be to minimized for the best results. Having very narrow front wheels minimizes the frontal area. This is the main reason why narrow front wheels are used. If the smaller the wheel the lower the drag, why not have the wheels narrow and very short as well? You ask. Well the reason is that if the wheels were very small they would drop into all the bumps and cause a loss of speed not to mention control. As the wheels would bounce into the depression and then launch up into the air as they come out of the bump. This is extremely dangerous in that the driver can no longer steer the vehicle that is travelling at near five hundred kilometres per hour, the car can also get air flowing underneath the car, with the effect of air resistance the car will lift up of the ground and flip through the air. Also the rotational force is much harder on the bearings causing more wear and friction meaning slower times. Large wheels are used because they will skim over the bumps and keep the car moving along a flat plane. They also exert less force on the bearings meaning less friction and better times. Now if drag cars use narrow front wheels so they can get less air resistance and a better top speed why don?t all racing vehicles run narrow front wheels? The answer is friction. The front wheels of drag cars do not have high cornering or driving force travelling trough them. I.e. they are only there to hold the front of the car up and allow it to roll along the road. In conventional racecars high forces are exerted on the tyre in the horizontal plane meaning that they need to have a good tread area so that they grip the road well and hold the car on the track so it does not slide off

Government and Non-Profit Organizations Essay Example | Topics and Well Written Essays - 250 words

Government and Non-Profit Organizations - Essay Example This will not only provide joint support but will initiate some other ways of improving tourism among the youths and the local people. Some of the governmental agencies which the organization can partner with include Ministry of sports and youth affairs, Ministry of tourism, as well as institutions of higher learning in Kenya. The above mentioned government agencies will be highly meaningful in giving support to the realization of the organization goal in various ways. Ministry of sports and youth affairs is in charge of sporting activities in the country as well as establishing the well-being of youths in the country. It therefore has the influence of youths towards visiting the parks. Ministry of tourism is in charge of promoting tourism in the national and international arena. This will provide an avenue for marketing the organization and formulating policies to the local people as well as to the youths hence creating awareness (Jones, 2005). Institutions of higher learning comprising of universities and middle colleges can arrange tour activities such as picnics and adventures to the Nairobi National Park as they are the centre of excellence where many youths are. Despite the efforts by Nairobi National Park to increase the number of local tourist, there are perceived conflicts which are to arise as it partners with government and other agencies. One of the potential conflicts is on the fee to be charged in the entrance. Most young adults do not have enough money to cater for the higher fees charged hence will conflict with the agencies which may introduce small fees. Additionally, the agencies may want to dominate through imposing policies against the organization. The clash in polices will pose a conflict between the organization and government

Nutrition - Ask and Answer - Characteristics of Life Essay

Nutrition - Ask and Answer - Characteristics of Life - Essay Example The following hypotheses were formulated: First, simple obesity among children is affected by the following environmental factors: educational levels of parents, familial inclination to obesity, and other health patterns. Secondly, a diet with low energy component and low glycemic index results into body mass loss. Thirdly, dietary treatment will involve change in the body mass, reduction in skin thickness and adipose folds, scapula, BMI, body fat content and waist hip ratio. Lastly, administration of dietary treatment will affect biochemical indicators like lipid profiles (Rozwoj, 2006). A sample size of 236 children with known simple obesity from Mazowsze region was used. The research was carried out by Gastroentorogical and Endocrinological Unit of the Institute of Mother and Child for10 weeks. Nutritional state was analyzed on the principle of investigating. Eight essential features and five anthropometric parameters were used besides common biochemical indicators for carbohydrate and fat metabolism. Evaluation was done prior to and after the commencement of the study. Studies were carried out on nutrition that comprised eating habits, composition of food, and the constituent nutritional content of food given daily covering a period of 10-14 for every child prior to the dietary treatment and 3 random days after. Collection of data on environmental factors was administered by a questionnaire (Rozwoj, 2006). It was found that environmental factors constituted major risk to obesity. A relationship was established between a normalized BMI z-score with respect to environmental factors which included paternal obesity (Chi (2) test with p-value less than 0.05). Also a positive correlation was found between relative BMI z-score and the anthropometrical factors. No distortions in carbohydrate metabolism were established except for fats (Rozwoj, 2006). The dietary treatment contained

B/M Ratio Essay -- Research Analysis

We can see from regression I of Panel A and B that B/M is highly significant relative to the future returns, which are consistent with the B/M effect theory. The B/M effect for NOA/P^NOAï ¹ ¤1 data also cannot be rejected for the ambiguous t-statistic. Similarly, the enterprise B/M ratio is confirmed by regression II. The testing results for one factor model of financial leverage (ND/M) presents that the financial leverage is not significantly relative to future returns, or even negatively relative to future returns. It is an anomalous phenomenon that the leverage (financial risk) reduces the expected returns, but it may be explained by the negative association between leverage and operating risk. Actually, these results are also consistent with also correlation analysis in Table 2. When NOA/P^NOA≠§1, leverage is positively and insignificantly relative to the NOA/P^NOA. However, when NOA/P^NOAï ¹ ¤1, leverage is negatively relative to NOA/P^NOA. Regression V shows the leverage coefficient under controlling for operating risk (enterprise B/M ratio). For full sample tests, the coefficient is insignificant which means we cannot get any reliable conclusions from this result. And for NOA/P^NOA ≠§1, the coefficient is insignificantly positive, for NOA/P^NOAï ¹ ¤1, the coefficient is significantly negative. If we split the ND/M ratio into financial liabilities/market value and financial assets/ market value like in regression VII, FA/P coefficients are significantly positive in all of three panels, but the FL/P negatively or insignificantly relative to future returns. It indicates that the high future return premium is awarded for the high operating risk rather than financial risk. As the financial leverage is insignificant in some regressions, we u... ...returns, and this association is even insignificant for most NOA/P^NOA portfolios. The only exception is in the highest two NOA/P^NOA portfolios, highest ND/M portfolios give higher returns than lowest ND/M portfolios. Similarly with US evidence, the findings in UK evidence suggest that the UK FTSE 350 stock returns are inconsistent with PRT’s equation 2. In Panel B of table 4, we use similar methods with Panel A to spilt the year-firm observations into 10 portfolios, and sort these observations into five groups by B/M ratio rather than leverage ratio. According to PRT equation 1, if NOA/P^NOA >1, a higher leverage ratio will lead to a higher B/M ratio; if (NOA )/P^NOA 1, a higher return the higher B/M ratio.

Describe the symptoms and treatment of asthma

Unfortunately asthma can be inherited and in many children asthma is diagnosed after having a cold or fever. Studies shows that a high percentage of these children, during their lifetime will have a higher chance of getting rid of the disease. On the other hand if asthma is inherited, most likely the patient will be diagnosed during his or her lifetime. According to statistics, asthma is one of the most common physiological disorders and it can affect all ages. Nowadays, we have specific treatments to control the disease but unfortunately, till now, there is no cure. One of the most important functions of the respiratory system is to breathe. Air is inhaled through the mouth or nose, it then moves through the pharynx, larynx and trachea into the lungs. After that process, the air is exhaled through the same pathway. During normal inhalation the external intercostal muscles and diaphragm contract and as a result of this the rib cage elevates. Due to this the volume of the lungs increases, air pressure drops so air rushes in. On the other hand during normal exhalation the muscles relax, lungs become smaller, air pressure rises and air is expelled. Asthma is a lung disease which narrows and inflames the air ways, we have tubes which they carry air into our lungs. When a person is diagnosed with asthma these tubes are inflamed. This inflammation makes the airways terribly swollen and sensitive. Due to this the inflammation starts reacting to certain substances that enter the airway. Once the airway starts reacting to these substances our muscles tighten up, as a result of this the airways are narrowed so less air enters to the lungs. Asthma has an impact on other body systems, these are the immune system, the nervous system and the respiratory system. Starting off with the first system, the respiratory system of a person with asthma is more sensitive to environmental irritants than of a normal person. When there is contact with an environmental irritant, automatically the airway narrows making it more difficult to breathe. Second system, the immune system, our immune system helps our body to fight germs. When a person is diagnosed with asthma, his immune system is more sensitive to substances that are not harmful to those who do not have asthma. The last system that I am going to explain is the nervous system. According to John Hopkins University â€Å"research indicates that asthma affects your nervous system, a nerve growth factor a nervous system protein, has been found to increase sensitivity to irritants among people suffering from asthma and allergies†. (Apryl Bevelery: 2014) In this paragraph I am going to mention and explain some asthma symptoms starting off with the first symptom wheezing. Wheezing is one of the most common symptoms, wheezing is a squeaky noise which is normally heard while the person is sleeping. Wheezing can be heard more during this period because the airway normally narrows during respiration. Wheezing happens because there is a narrowing or obstruction from the level of the larynx to the small bronchi. According to studies, wheezing is said to happen by oscillations and vibrations of the airway walls. This sound is formed when air passes through a narrowed portion of the airway, then air passes with high velocity producing a decrease in gas pressure which later on it is flown in the constricted region. Once it arrives in the internal airway the pressure begins to increase which will be barely able to reopen the airway lumen. A second symptom coughing, a person diagnosed with asthma can suffer from coughs during an asthmatic attack, one can think that coughs are painful but it is a natural reflex which protects our lungs. This happens by clearing foreign substances that our body does not want. This process starts by, when an unwanted substance enters, our nerves sends an electric impulse to the brain to tell our muscles in our chest and abdomen to contract against these substances. When the nerve endings of our airways become irritated coughs usually occurs. After this contraction it will release large amounts of air and high amount of strength to eject these substances. There are different types of coughs namely chronic and acute. Chronic cough means that the cough will stay longer, most probably this is due to a medical condition. While acute cough means that the cough happens only at that moment. The last symptom that I am going to mention is chest tightness and shortness of breath, these are also common symptoms. A patient who is not diagnosed with asthma has a clear bronchiole wall, this wall will be relaxed and provides an open airway. On the other hand a patient with asthma will be very sensitive to irritants, as a result of this when an irritant occurs most probably it will inflame this wall. A list of these irritants can be smoke, stress, dust mites, infections and many more. Due to these problems such as releasing leukotrienes, result of this an inflammation may occur which unfortunately will lead to overproduction of mucus. Overproduction of the mucus will result in constriction in the bronchiole making it difficult for air to move in the lungs. As a result of this an asthmatic attack can occur. There are specific factors which may result in triggering asthma, starting off with the first factor which is environmental. Nowadays we live in an environment which has a high amount of pollutants such as, flower scents, mould, pests, dust mites, tobacco, animal dander, car pollution, extreme weather and many more. There are certain factors that we can control especially those that we can find indoors. Those that are found indoors can be controlled in order to avoid asthma triggers, an example of this can be cleaning weekly, keeping pets out of rooms, removing carpets, servicing the air conditioners and vacuuming. Second factor can be allergies, unfortunately an allergic reaction can be similar or the same in order to trigger an asthma attack. According to studies being overweight will result in more chronic low-grade systemic inflammation, which means that the patient will suffer from inflammation throughout the body. Last factor that I am going to explain is smoking, this can affect an asthmatic person because when a person inhales tobacco, irritations substances will lay out in the moist lining on the airways. These irritants can trigger an asthma attack. Nowadays thanks to scientists we are developing more and more tests in order to be able to diagnose diseases in their early stages. Starting off with the first test spirometry, this test is often used to assess the patient’s lungs. The procedure of this test is to take deep breathes and exhaling it as fast as they can through a mouthpiece attached to this equipment. This test consists of two measurements, these are the volume of air breathed in and the volume of air breathed out. Normally this test is done many times to get accurate results. Second test peak expiratory flow test, this test is done by a device called peak flow meter. This is a very easy test, it measures how fast the patient can blow air out of his/her lungs in only one breathe. Most of the time this test occurs over weeks, in fact the patient needs to take this device home so she/he can record daily measurements. The patient needs to take this device with him or her because asthma can be vary due to changes in our lungs throughout the day. Third test airway responsiveness, this is a difficult test in fact this test occurs only if there are no clear symptoms of asthma. The airway responsiveness test measures how the airway reacts when it is contacted with a trigger. During this test the patient is asked to breathe in medication, which will eventually irritate the airways and possibly trigger a mild asthma attack. Another test that can be done is testing airway inflammation, this test can be done by two different methods. The first method is to take a phlegm sample and the second method is while the patient is breathing out, the level of the nitric oxide is measured. An allergy test can also be done in order to confirm if the person’s asthma is associated with any allergies. Imaging tests are also an alternative, these can be a CT-scan or a chest x-ray of the patient nose cavities and lungs. With these scans they can identify any abnormalities related to asthma. The last test that I am going to mention is the sputum eosinophils, the main role of this test is to look for white blood cells while the patient is coughing. The white blood cells are present when symptoms occurs which later on are visible when they are stained with eosin. Fortunately there are certain treatments that help prevent and control asthma, starting off with the first treatment inhaled corticosteroids are preferred methods for long-term control of asthma. The main function of this treatment is to relieve inflammation and swelling, reducing inflammation helps to prevent asthma attacks. Another treatment which is given during an asthma attack is cromolyn, this medicine is given when the patient is using the nebulizer. Once the patient breathes in, the nebulizer will send medicine to the lungs to prevent airway inflammation. Omalizumab is a medicine given as an injection one or two times a month, this medicine helps to prevent our body from reacting to asthma triggers. Inhaled long-acting beta2-agonist and theophylline are all medicines that open the airways. The leukotriene modifiers are a medicine take orally, this helps to prevent increase of inflammation. Then there is the quick-relief medicine these are called inhaled short-acting beta2-agonisits these act quickly in order to relax tight muscle, this allows to open airways so air can flow through them. A patient who is diagnosed with asthma needs to have frequent check-ups, it is also very important to remove any items which can trigger asthma such as rugs or animals. It is also recommended to record your symptoms in a diary to see how well the treatment is controlling your asthma. Good control of asthma will prevent coughing and shortness of breath, reduce the use of quick relief medicine, help to maintain good lung function, prevent asthma attacks and let the person maintain the normal activity of sleeping throughout the night. It is also very important to use proper asthma medications as like with other medications they have side effects. When a person starts having these symptoms it is very important to do a check-up or talk to someone else because if these signs are not treated asthma triggers can worsen which even in some cases can be fatal.

The Politics Of State Matters - 1665 Words

I have never really been a person for politics. It always seemed too easy to see people go into heavy defense mode to prove their points in an indecisive audience and try to share their opinions as facts. Meaningless arguments and pointless feuds start over miniscule topical topics. Fortunately in the area of anthropology, politics comes at a different context than to save its’ usual position for voting or presidential races. In anthropology, I learned about the politics of state matters. Finding out more than leadership but what keeps a group or community together or can tear citizens apart. I am a person who has dealt with projects of direct observation. There’s something inherently interesting from looking at interactions and the†¦show more content†¦I was hopeful that my time observing for APO and its members for a meeting could change my prejudice. For materials, the subjects of this observational study were all of the members in the room but I paid a lot of attention to the Eboard staff. These were all college students that varied in age and college level of freshmen to senior but still in their early to late twenties. The Eboard officers consisted of the President, the Vice President of Service, Director of Communications, Secretary, Sergeant of Arms, Treasurer, Vice President of Membership, Vice President of Fellowship, Pledge Trainer, Conference Chair, and Historian. I had learned that all of the Eboard attend each meeting. The fraternity has both associates and active members. There are a majority of the active members are in the head and represent some of the leadership roles in APO. And even inactive members who are still apart of APO but take time off due to other activities or things happening in their lives where they can’t devote a lot of their time to earning points for service, fellowship, leadership, etc. Because APO was made before women were allowed to join in 1974, APO members would call each and themselves, â€Å"brother† to show a family like closeness to the Roosevelt male students in the past school decades. Even in today’s current age, â€Å"brother† is still a term of endearment even when said to the large female majority in the club. The past Monday went fine with

10 Russian Terms of Endearment