Energy and Block Essays

Energy and Block Essays Energy and Block Paper Energy and Block Paper Assignment Physics 1 1 . Two carts, one twice the mass of the other, experience the same force for the same time. What is their difference in momentum? What is their difference in kinetic energy? 2. A 12 g bullet is fired horizontally into a 96 g wooden block initially at rest on a horizontal surface. After impact, the block slides 7. 5 m before coming to rest. If the coefficient of kinetic friction between block and surface is 0. 60, what was the speed of the bullet immediately before impact? You have to use the conservation of the total energy of the system to do this problem: Initially, you have, in the total of your system, a bullet that is moving at a certain speed and a block that is stationary: Initial total energy = Potential Energy + Kinetic Energy + Elastic Energy There is no potential energy nor is there a spring in the system so no elastic energy. Initial total energy = Kinetic Energy. Since the only thing that is moving in the system is the bullet, then you calculate the kinetic energy of the system at the initial state (before the bullet hits the block): Kinetic energy = 1/2mv2 where m = 0. 012kg so kinetic enery = . 5 * 0. 012 * 0. 6v2 We dont know the initial velocity of the bullet because that is what we are trying to find. Now, you say that Initial Energy of the system = Final energy of the system because no Energy is lost or created, all energy is merely transfered or transformed. Initial Energy = Final Energy Final Energy: At the end, you have: A block with a bullet lodged inside it that is not moving. Therefore No Kintetic Energy, No Pot ential Energy and no Elastic Energy. However, your block did Work in order to combat the friction force and to move the block over a distance of 7. 5 meters. This energy was lost in the friciton and was expulsed as heat when the block was moving. So final Energy = Work done to move the block from O to 7. 5 meters. Work = Force * distance where distance is 7. 5 meters The force is the friction force because that is what the block had to combat in order to move. Friction force = u*N N = (mass of bullet + mass of block)* 9. 81 u = 0. 65 F = 0. 65 * 0. 012 * 0. 1 * 9. 81 = 7. 23918 Newtons = 7. 24 N Work = Force * distance = 7. 24 * 7. 5 = 54. 3 Joules So initial energy = final energy 0. 006V2 = 54. 3 v2 = 9050 v = 95. 13148795220224032296947867491 v = 95 m Is So the bullet was moving at 95 m/s right before it hit the block. 3. A ball bounces upward from the ground with a speed of 14 m/s and hits a wall with a speed of 12 m/ s. How high above the ground does the ball hit the wall? Ignore air resistance. 4. A 200 g mass is attached to a spring of spring constant k. The spring is compressed 15 cm from its equilibrium value. When released the mass reaches a speed of 5 m/s. What is the spring constant (in N/m)? 5. A 34-g bullet traveling at 120m/s embeds itself in a wooden block on a smooth surface. The block then slides toward a spring and collides with it. The block compresses the spring (k=100 N/m) a maximum of 1. 25 cm. Calculate the mass of the block of wood. 6. If a force of 300N is exerted upon a 60 kg mass for 3 seconds, how much impulse does the mass experience? 7. An 80-kg man and his car are suddenly accelerated from rest to a speed of 5 m/s as a result of a rear-end collision. Assuming the time taken to be 0. 3s, find: a) the impulse on the man and b) the average force exerted on him by the back seat of his car. 8. An airplane propeller is rotating at 1900 rev/min. a. Compute the propellers angular velocity in rad/s. b. How long in seconds does it take for the propeller to turn through 30. 0 degrees? 9. A disk with a 1. 0-m radius reaches a maximum angular speed of 18 rad/s before it stops 30 revolutions after attaining the maximum speed. How long did it take the disk to stop? 10. A net torque of 36 N. m acts on a wheel rotating about a fixed axis for 6 s. During this time the angular speed of the wheel increases from O to 12 rad/s. The applied force is then removed, and the wheel comes to rest in 75 s. a. What is the moment of inertia of the wheel? b. What is the magnitude of the frictional torque? c. How many revolutions does the wheel make?

Scams, stealing, theft Research Paper Example | Topics and Well Written Essays - 2000 words

Scams, stealing, theft - Research Paper Example obbery (application of force in order to steal from someone), copyright theft (non-physical theft, of ideas/ thoughts), retailing theft (shoplifting), credit card theft, embezzlement, possession of stolen material, forgery, identity theft, and so on. Stealing is an offense that results in punishments such as fines and jail terms. In the contemporary society, theft is fast becoming the number one global crime with surveys indicating that over a quarter of jailed person in major world nations are serving time in prisons on theft related convictions. This is not to mention the numerous cases that often go unreported or un-noticed by the law. One of the most notorious kinds of theft in the present age is shoplifting. Shoplifting refers to the removal of an item (goods) from a sales shop (shop) without paying for it. There are several questions that continue to trouble mankind concerning the crime of theft. What really triggers a person to steal? Is there a specific age in which one is transformed into a thief? Who is to blame for the alarming increases of theft cases around the world? What can be done to curb the tendency to steal? This essay attempts to answer these questions in a fair, well-informed and well-supported way using expert opinions, experiences and global surveys. As per the results of Jack L. Hayes International’s 26th Annual Retail Theft Survey, approximately 1.2 million dishonest workers and shoplifters were caught in the year 2013 in the United States alone. Equally more surprising is the fact that these apprehensions were done in only the 23 retail companies that were surveyed with more than USD 200 million recovered from these thefts. These figures continue to rise yearly and were noticeably higher than the statistics for the previous year, 2012. With increasing retail thefts, shop owners are facing huge annual loses with the innocent consumer forced to pay higher prices for goods in order to cover the losses from theft. This theft thus results

What is politics Essay Example | Topics and Well Written Essays - 500 words

What is politics - Essay Example The initial philosophy is easy for many people to agree that anguish and death have nothing to do with great things. The second philosophy can be illustrated with the example that Singer provides that if we were in a situation where we take a rail switch and divert a train thus saving a child’s life or act like Bob who decides to throw away the train switch to save his Bugatti. In a nut shell, Singer is trying to say that stopping something bad from taking place will at all times lead to destroying something material or spending cash on something meaningless.Depending on these two philosophies enables Singer come up with his conclusion at the end of his line of reasoning. Singer initially indicates that there are individuals in East Bengal who suffer and die from food deficiency and shelter which is trailed by his philosophy. When Singer mentions his 2 philosophies at first makes it easy to understand and in fact agree with his line of reasoning. However, his conclusion is act ually not convincing enough. Singer claims that it is undisputable that when money is sent to charity, life will be saved and people will be elevated from poverty. However, it is also evident that no matter how much we try to help the needy by donating some money, the global poverty will not end. This is, even if we send a lot of cash to poor countries, we will end up doing this for the rest of our lives. In due course, with never ending donations and charity work, it is evident that this will lead to immense depression and untold suffering.

Forensic Entomology research paper Example | Topics and Well Written Essays - 1500 words

Forensic Entomology - Research Paper Example It was not until 1668 that Francesco Redi disproved this by observing how these creatures developed into flies, and much later, in 1894 that Megnin developed a method to link this process with a method for calculating the age of a dead body (Byrd and Castner, p. 41). Throughout the twentieth century scientific methods of analysis have improved greatly, with the result that at the present time forensic entomology is a well-established discipline within forensic science, complete with rigorous protocols and extensive underpinning research which help to ensure that it provides relevant, accurate and reliable evidence for crime investigation and prosecution purposes. Forensic entomology is therefore a dual discipline combining elements of natural science in the methods of collection and analysis of samples, and elements of criminology, in the interpretation and application of results, and in the preservation of evidence which is reliable enough to stand up to scrutiny in the criminal jus tice system. Although these two areas have a different focus, they are closely aligned in crime investigation procedures, requiring collaboration across disciplines according to clear scientific principles. This paper explores the contribution that forensic entomology makes to crime investigation and prosecution by examining three of its major areas of application: 1. Determining the post mortem interval (PMI); 2. Providing human DNA linkages and 3. Providing toxicology information. A number of limitations as well as legal and procedural issues are covered also in section 4. 1.Determining the Post Mortem Interval (PMI) through forensic entomology. 1.1 Species involved. Corpses provide a very specialized ephemeral environment which is colonized by particular communities of arthropods in a predictable manner, with one species following on after another in a process known as â€Å"succession† (Horswell, 2004, p. 347). The main species The first species to arrive, often within mi nutes of death, are blowflies. Blowflies from the Calliphoridae family are generally the first stage invaders, and then after these others follow Sarcophagids which constitute a second stage, often overlapping with the first stage somewhat. After this follow the third stage Muscids and Piophilids (Horswell, 2004, p. 348). 1.2 Types of information obtainable. Scientists are able to obtain good information from a corpse soon after death, by taking photographs, measuring temperature, observing rigor mortis and any wounds, and conducting various other tests on the tissue. With increasing passage of time, however, the tissue degenerates, and it is more difficult to obtain reliable data. Because the life cycle of insects is known, and the effects of temperature and weather can be factored in to the equation, careful collection of insects at the scene can provide useful estimate of the PMI. Empirical work in the laboratory has established standard growth times for many of the most common c arrion feeding species, and this means that the determination of PMI has become the most used application of forensic entomology in modern crime scenes (Nabity et al. 2006, p. 1276). Another useful piece of information that can be obtained from examination of species present in a corpse is the whether or not the body has been moved.

Acknowledgement- master dissertation Essay Example | Topics and Well Written Essays - 250 words

Acknowledgement- master dissertation - Essay Example XXXX taught me that to learn is to constantly challenge what I have learned. It was only through his support and persevering patience that I found the courage and will to overcome the many obstacles and vicissitudes on my way to finishing this dissertation. - My professors, XXXX and XXXX, for their helpful comments and insightful critique in guiding me through the techniques of dissertation writing and choice of topic. Their pragmatic realism coupled with constant encouragement allowed me to grow in both knowledge and character. - My beloved father, Dr. XXXXX, who stands as my role model in both my personal and academic life, for his unwavering support and prayers for my wellbeing and success, and for always being there for me; - My mother, my first and wisest teacher, for raising me to value knowledge and virtue, and for standing by me and encouraging me with her sweet words and unshakeable faith in my eventual success, not only in my graduate studies, for in everything I pursue in life. - My dear husband, XXXXX, for being the wind beneath my wings, and for being the wellspring of support and patience I needed to forge on. It is his belief and trust in me that saw me through the most difficult times in the course of my graduate

Stakeholders in Health and Safety Duties at Work

Stakeholders in Health and Safety Duties at Work Client The client has responsibilities on a work site. The client is responsible for checking the competence of all the appointees and their resources. They must make sure that the facilities for all of the workers are suitable for their welfare. They must allow sufficient resources and time for each stage in the project and not rush any of the project. They must also provide information to the designer and contactors before the construction. The client is also responsible for hiring a CDM co-ordinator and a principle contractor. They must also make sure that the construction doesnt start unless the construction phase is complete and all of the welfare facilities for the workers are on site, provide a health and safety information file for the CDM co-ordinator and retain and provide access to the health and safety file. CDM Co-ordinator A CDM co-ordinators main duties are to advise and assist the client with their duties, to keep the HSE notified of the project details. Cooperate with everyone involved in the design and coordinate all of the health and safety aspects of the design. Facilitate good communication between the designer, contractor and client. Communicate and meet with the principle contractor regarding the design work. Analyse, gather and convey pre-construction information. And to prepare and keep the health and safety file up to date. Architect The architect is responsible for making sure that there will be no risks or hazards whilst still in the design stage of the build. After that is done they must provide information on all the other risks that there could still be and that cannot be completely prevented. The architect must make sure that the client is aware of their roles and responsibilities during the design stage and the construction phase of the whole process; they are also responsible for making sure that the client has hired a CDM coordinator. They must also provide information for the health and safety file and also keep the file updated. Workers Workers have health and safety responsibilities on site, as they are the most likely to be involved in an accident they also have dutys to health and safety. The workers must be competent and know what they are doing at all times. They must report any obvious risks that they see in a site so that accidents can be avoided. Coordinating their work and cooperating with all of the workers to ensure you own and everyone elses health and safety. They must also follow the health and safety rules and procedures and be aware of any hazards there could be on a site. P2 Outline the legal duties of employees and employers in relation to three pieces of health, safety and welfare legislation relevant to the construction and built environment sector Legislation in health and safety are very important as they can help protect people from accidents and keep them safe in the working environment. This also covers people who arent part of the building companys employment. There are many different legislation which all protect different areas of work. Legislations like the Health and Safety at Work Act 1974 (HASAWA), Working at Heights 2007 (WAH), Control of Substances Hazardous to Health 2002 (COSHH). The HASAWA is a very important legislation that was introduced in 1974 and many other pieces of legislation have been developed from this act. The HASAWA covers the duty of care that is on a construction site. There has been a large amount of health and safety legislation that has been created since HASAWA. It covers the occupational health and safety in Great Britain. Health and safety executives and other enforcing bodies are responsible for the administration of the legislation. The employer has responsibilities that they must follow out so that employees are safe. The employer must ensure health, safety and welfare at work to all of their employees. The employer must prepare a written statement of their general health and safety policy. They are also responsible for the enforcing of safety and reduce the risk to health involved in all the employees areas. The employee also has duties that they must follow out. The employees must take reasonable care in their safety and the safety of those around them who may be affected by their actions. They must also cooperate with the employer so that requirements can be met. COSHH is another important piece of legislation that is used in construction. This legislation helps to protect then workers from handling substances that could be fatal. The legislation ensures that the harmful substances will be supressed so that it is less of a risk to the employees. The legislation also states that employees must be informed about the substance and should have their health monitored if work with hazardous substances. Many businesses use substances that can be harmful to workers and these businesses should inform and train employees so that the substances can be handled. The employee has duties that they must carry out whilst enforcing the COSHH act. They must make sure that the substance has had a proper assessment identifying the risks that this substance may have on the heath of anyone involved, the assessments must also be updated if they become invalid or out dated. Substances that have a COSHH warning label must be stated in the inventory and material safety data sheets. The employees must also be train, supervised and instructed on the risk that the substance could have on the health of the employees and the precautions that must be taken. The employees also have duties that they must follow according to the COSHH act. Employees must know the hazards substances that are present and read the signs that are present at the work site and should handle the substances safely and follow the instructions given. They must ensure that the warning labels are left on the containers and inform management of and situation involving the substances that could be dangerous. The final legislation is the WAH. This act is a law. This legislation ensures that before workers start working at a height the working must be planned and organized, the workers must be competent. The work must be assessed before the workers go up and the equipment that they are using must be the correct equipment. The risk of surfaces that may be fragile should be controlled and supported and the equipment that is used must be properly inspected and maintained. The duty holder must be responsible for the legislation being put into practice. The employer must ensure that all of the work is planned and organized and is carried out by a competent employee. The employees must receive information, training and instruction on how to safely use the equipment and how to spot defects in the equipment. They must follow the hierarchy of controls and they must do as much as they can that is practical to stop workers from falling. Employees must report and possible hazards or faulty equipment t o the employer and they must use the equipment supplied and follow instructions correctly and safely.

The Curriculum Guidance for the Foundation Stage Essay -- Papers

The Curriculum Guidance for the Foundation Stage Consider how your placement setting was effective in meeting the learning needs of all the children, with specific reference to: 1. Communication, Language and Literacy 2. Mathematical Development 3. Knowledge and Understanding of the World In this assignment I will explain what I understand the Curriculum Guidance for the Foundation Stage to be about. I will also describe the nursery setting in which I was placed and discuss if it was effective in promoting a positive learning environment. My 3-5 placement was based at Gorse Hall Nursery in Stalybridge. And finally I intend to discuss how the nursery setting encouraged the children to develop their learning in Communication: Language and Literacy, Mathematical Development and Knowledge and Understanding of the World. I will draw upon my observations, experiences and study tasks to discuss my understanding of the Foundation Stage. According to Keating, I, (2002), â€Å"†¦the Foundation Stage is crucial in helping every child to develop skills, knowledge and understanding, attitudes and concepts which will prepare them not only for entry into full-time school but for the rest of their lives.† Children are already bringing with them a range of experiences and personal interests from home and it essential that the teacher discover these and implement them into their planning. Gorse Hall Nursery follow a school policy which suggests that teachers develop a partnership with parents. Parents are encouraged to come in to nursery and talk to staff if they have any concerns. They are also involved in their child’s learni... ...ctive to teach something that the children have no experience of. Then ensuring they are planned within a context e.g. Autumn, fruit and veg. Making them enjoyable. Compare and contrast children’s behaviour/ responses/attitudes in the morning and in the afternoon. What do you notice? The children are different in the afternoon so it is difficult to compare behaviour. The afternoon children have more problems with concentration, especially at story time when they fidget a lot more. The afternoon children need more supervision than the morning children. Does the planning reflect children’s responses in the morning and afternoon? Task five continue†¦ The planning is the same in the afternoon as the morning but is executed a little differently according to the temperament of the children.