Marketing and Converse Question Essay Example for Free

Marketing and Converse Question Essay Need: Protection for the feet Wants: Cheap shoes which are comfortable and customizable. Demands: Emerging artists, designers and musicians wearing Chucks because of their affordability, simplicity and classic look. Now, anti-establishment rock fans beg Converse to feature a shoe by their favourite artist. Question 3 Production concept: The idea that consumers will favour the products those are available and highly affordable, and the idea that the company focus on improving production and distribution efficiency. Product Concept: Costumers will favour the products that offer the most quality, performance and features. Therefore the company should focus on making constant product improvements Selling Concept: The idea that consumers will not buy enough of the products unless it undertakes a large-scale selling and promotion effort. Marketing concept: The marketing philosophy that holds that achieving organizational goals depends on knowing the needs and wants of target markets and delivering that desired satisfaction better than competitors does. Almost every red Chuck converse sold goes to Global Fund. Question 4 Converse sees its role as one of making great products that its costumers want to wear. Beyond that it participates in consumers discussions rather that dictating them. Drawbacks: Converse rides a fine line: How many limited editions and upscale design can the brand produce without losing its image as a non marketing marketer. How popular can the brand become without losing the core costumers who love the precisely because it isn’t popular Question 5 Converse has been very careful in all that it does to remember on very important things for a brand like Converse, where authenticity is the most important trait, the costumer experience should be driven by the costumer.

Engine Cooling And Lubrication System

Engine Cooling And Lubrication System Cooling System: Despite the vast improvement in the basic internal combustion engines, around 70% of the energy from the gasoline is converted to heat. As it is not dissipated to the atmosphere on its own, a cooling system is employed for this purpose. Several purposes of the cooling system which it serves by cooling the engine include cooling the engine to keep it from overheating by transferring the heat to the air. This helps avoid the excessive wear and tear at high temperatures, auto-ignition due to hot cylinder which may result in knocking and hence, piston/cylinder failure. It may also incorporate thermal stresses which is not good for the engine itself. Figure . Cooling system and plumbing connection While it serves the purpose of cooling the engine, it also helps the engine to warm up quickly during cold start ups and then maintaining a constant temperature. When the engine is cold, components wear out faster too and the engine is less efficient, emitting more pollution. Types of Cooling System: There are two types of cooling systems found in cars: Air-cooled Liquid-Cooled Air-Cooled Engines: Many small and the medium-sized engines are air-cooled. This category includes most small engines like lawn mowers, chain saws, model airplanes etc. Using the air-cooled system allows both the weight and price of the engine to be kept low, along with reduced complexity of the machine. The air-cooled system is still widely used on most of the motorcycles in use these days. This system utilizes the concept of heat transfer through fins to cool the engine. The cross-sectional area of the fin being larger closer to the head and a reduction in the area as we move further from the engine block. The basic principle on which the air-cooled engines rely on is the flow of air across their external surfaces to remove the excess heat to keep the engine from overheating. The airflow on machines like motorcycles and aircrafts is provided across the surface when the vehicle moves forward. Deflectors and ductwork is incorporated to direct the airflow to the critical locations where more cooling is required. The outer surface of the engine is made from a good conductor of heat and the surface is finned to promote maximum heat transfer, along with which an extra fan is used to increase the air-flow rate; whereas others use the concept of free-convection. These fins are to be properly designed for appropriate cooling effect which is required. Some automobile engines also use exposed flywheels with air-deflectors fastened to the surface. When the engine is in operation, these deflectors create air motion which increases the heat transfer on the finned surface. Even after considering and applying all the measures, the uniform cooling of cylinders is still difficult to achieve on air-cooled engines as compared to the liquid-cooled engines. The figure below shows that the cooling needs are not the same at all the locations. Figure . Variation of heat losses from the fins of an air-cooled aircraft engine. Seventy-one percent of the heat losses occur on the hotter side of the cylinder, containing the exhaust valve. The engine shown was used on a number of different aircrafts. Hotter areas, such as the ones around the exhaust valve and manifold need greater cooling and hence larger finned surface area. Cooling the front of an air-cooled engine which faces the forward motion of the vehicle is much easier and efficient as compared to the back surface of the engine. This may result in temperature differences and thermal expansion problems. Disadvantages: Disadvantages of air-cooled engines are that they: Are less efficient, Are noisier, with greater air flow requirements and no water jacket to dampen the noise, Need a directed air flow and finned surfaces. Advantages: When compared with liquid-cooled engines, air-cooled engines have the following advantages: They are lighter in weight, They cost less, No coolant system failures (e.g., water pump, hoses), No engine freeze-ups, and Faster engine warmup. Liquid-Cooled Engines: In a liquid or water-cooled engine, the engine block is surrounded by a water jacket through which the coolant flows. This allows for a better control of the heat removal from the engine, just by added weight and a more complex system. Very few water-cooled engines use just water as the cooling fluid in the water jackets; this is because the water has a freezing temperature of 0Â °C which is unacceptable as coolant in colder regions, so additives are usually used for better performance. Although water has very good heat transfer properties, but when used alone, it causes rust and corrosion in many of the pipes of the cooling system. Ethylene glycol (C2H6O2) is the antifreeze agent which acts as a rust inhibitor and a lubricant for the water pump. When added to water, it lowers the freezing temperature and raises the boiling temperature of the coolant. The properties of the mixture depend on the ratio in which water and the antifreeze agent are mixed. Pure ethylene glycol should not be used, and even at high concentrations the heat transfer properties of the water are lost as well. The properties of the ethylene glycol water mixture are shown in the table below. In addition to good thermal properties, a coolant should satisfy the following requirements: 1. Chemically stable under conditions of use 2. Non-foaming 3. Non-corrosive 4. Low toxicity 5. Non-flammable 6. Low cost Most commercial antifreezes satisfy these requirements. Many of them are basically ethylene glycol with small amounts of additives. Some commercial engine coolants use propylene glycol as the base ingredient. It is argued that when coolant systems leak or when the coolant becomes aged and is discarded, these products are less harmful to the environment than ethylene glycol. Basic Components: The basic components of a liquid-cooled system is shown below. Figure . Basic liquid-cooled system radiator radiator top hose radiator bottom hose water pump thermostat thermostat housing electric cooling fan thermo-time switch Radiator: The radiator is the part of the cooling system which is responsible for the heat rejection from the coolant and into the atmosphere. The radiator core is usually made up of flattened tubes with aluminum strips (fins) that zigzag between the tubes. These fins effectively transfer the heat contained in the coolant into the air stream to be lost into the atmosphere. On each end of the radiator is a tank made up of plastic to cover the ends. The tubes either run horizontally or vertically between the two tanks. The aluminum-plastic system is more efficient and cost effective. On radiators with plastic end caps, there are gaskets between the aluminum core and the plastic tanks to seal the system and keep the fluid from leaking out. The tanks have a large hose connection, one mounted towards the top of the radiator to let the coolant in, the other mounted at the bottom of the radiator on the other tank to let the coolant back out. On the top of the radiator is an additional opening that is capped off by the radiator cap. Another component in the radiator for vehicles with an automatic transmission is a separate tank mounted inside one of the tanks. Fittings connect this inner tank through steel tubes to the automatic transmission. Transmission fluid is piped through this tank inside a tank to be cooled by the coolant flowing past it before returning to the transmission. Radiator Fans: One or two electric fans are mounted on the back of the radiator close to the engine. These fans used the concept of forced convection to cool the heated coolant going through the pipes in the radiator core. If noticed, this fan starts working once the engine reaches a predefined temperature, after which the cooling by just natural convection during the forward motion of the car cannot be achieved. In the cars with air conditioning, there is an additional radiator mounted in front of the normal radiator. This radiator is called the air conditioner condenser, which also needs to be cooled by the air flow entering the engine compartment. As long as the air conditioning is turned on, the system will keep the fan running, even if the engine is not running hot. This is because if there is no air flow through the air conditioning condenser, the air conditioner will not be able to cool the air entering the interior. Pressure cap reserve tank: The pressure cap is simply a cap which maintains the pressure in the cooling system up to a certain point. If the pressure builds up higher than the set pressure point, the spring loaded valve releases the pressure. Figure . Pressure cap When the pressure in the cooling system reaches the point when the cap needs to release this excess pressure, some amount of coolant is bled off. The coolant which is bled off goes into the reserve tank which is not pressurized, which causes a partial vacuum in the cooling system. The radiator cap on these closed systems has a secondary valve which allows the vacuum in the cooling system to draw the coolant back from the reserve tank into the radiator. Coolant Pump: It is a simple pump which helps in circulation of the coolant around the system. This pump is run using one of the following: A fan belt that will also be responsible for driving an additional component like an alternator or power steering pump A serpentine belt, which also drives the alternator, power steering pump and AC compressor among other things. The timing belt that is also responsible for driving one or more camshafts. The impeller of the pump uses centrifugal force to draw the coolant in from the lower radiator hose and send it under pressure to the engine block. A gasket seals the water pump to the engine block and prevents the flowing coolant from leaking out where the pump is attached to the block. Thermostat: The thermostat is simply a valve that measures the temperature of the coolant, and if the coolant is hot enough it opens to allow the coolant to flow through the radiator otherwise the flow to the radiator is blocked and the fluid is directed to a bypass system that returns the coolant to the engine. Figure . Thermostat The engine is at times allowed to run at higher temperatures of 190-195Â °C; this reduces emissions, moisture condensation inside the engine is quickly burned off improving engine life, and a more complete combustion improving fuel economy. Oil as a Coolant: The oil when used to lubricate the engine also helps to cool the engine. The piston for example gets very little cooling from the coolant in the water jacket or the externally finned surface, so when the back surface of the piston crown is subjected to the oil splash or flow the piston is cooled to some extent. This is very necessary as the piston is one of the hottest elements in the engine. Usually, the oil is sprayed in pressurized systems, and splashed in non-pressurized systems. The oil acts as the coolant on the back face of the piston crown as it absorbs energy and then runs back into the larger reservoir where it mixes with the cooler oil and dissipates this energy into the other engine parts. This splash cooling of the piston is extremely important in small air-cooled engines as well as in automobile engines. A few other engine components other than the piston are also cooled by oil circulation, either by splash or by the pressurized flow from the oil pump. Oil passages through internal components like the camshaft and connecting rods offer the only major cooling these parts are subjected to. As the oil cools the various components, it absorbs energy and its temperature rises. This energy is then dissipated to the rest of the engine by circulation and eventually gets absorbed in the engine coolant flow. Some high-performance engines have an oil cooler in their lubricant circulation system. The energy absorbed by the oil as it cools the engine components is dissipated in the oil cooler, which is a heat exchanger cooled by either engine coolant flow or external air flow. Oil Pump: The gear-type oil pump has a pair of meshing gears. The spaces between the teeth are filled with oil when the gears unmesh. The oil pump obtains oil from the oil pan and sends oil through the oil filter to the oil galleries and main bearings. Some oil passes from the holes in the crankshaft to the rod bearings. Main bearings and rod bearings are lubricated adequately to achieve their desired objectives. In the rotor type oil pump, the inner rotor is driven and drives the outer rotor. As the rotor revolves, the gaps between the lobes are filled with oil. When the lobes of the inner rotor move into the gaps in the outer rotor, oil is forced out through the outlet of pump. An oil pump can also be driven by a camshaft gear that drives the ignition distributor or by the crankshaft. Oil Pan: Oil also flows to the cylinder head through drilled passages that make up the oil gallery, lubricates camshaft bearings and valves, and then returns to oil pan. Some engines have grooves or holes in connecting rods, which provide extra lubrication to pistons and walls of cylinders. Oil Cooler: Oil cooler prevents overheating of oil, by flow of engine coolant past tubes carrying hot oil. The coolant picks excess heat and carries it to the radiator. Oil Filter: The oil from oil pump flows through oil filter before reaching the engine bearings. The oil filter retains the dirt particles and allows only clean filtered oil to pass. The Lubrication system and its types: There are three basic types of oil distribution systems used in engines: Splash, Pressurized, or A combination of these. The crankcase is used as the oil sump (reservoir) in a splash system, and the crankshaft rotating at high speed in the oil distributes it to the various moving parts by splash; no oil pump is used. All components, including the valve train and camshaft, must be open to the crankcase. Oil is splashed into the cylinders behind the pistons and onto the back of the piston crowns, acting both as a lubricant and a coolant. Many small four-stroke cycle engines (lawn mowers, golf carts, etc.) use splash distribution of oil. An engine with a pressurized oil distribution system uses an oil pump to supply lubrication to the moving parts through passages built into the components. A typical automobile engine has oil passages built into the connecting rods, valve stems, push rods, rocker arms, valve seats, engine block, and many other moving components. These make up a circulation network through which oil is distributed by the oil pump. In addition, oil is sprayed under pressure onto the cylinder walls and onto the back of the piston crowns. Most automobiles actually use dual distribution systems, relying on splash within the crankcase in addition to the pressurized flow from the oil pump. Most large stationary engines also use this kind of dual system. Most aircraft engines and a few automobile engines use a total pressurized system with the oil reservoir located separate from the crankcase. These are often called dry sump systems (i.e., the crankcase sump is dry of excess oil). Aircraft do not always fly level, and uncontrolled oil in the crankcase may not supply proper lubrication or oil pump input when the plane banks or turns. A diaphragm controls the oil level in the reservoir of a dry sump system, assuring a continuous flow into the oil pump and throughout the engine. Figure . Lubrication of an engine consisting of a combination of a pressurized system and splash system Oil pumps can be electric or mechanically driven off the engine. Pressure at the pump exit is typically about 300 to 400 kPa. If an oil pump is driven directly off the engine, some means should be built into the system to keep the exit pressure and flow rate from becoming excessive at high engine speeds. A time of excess wear is at engine startup before the oil pump can distribute proper lubrication. It takes a few engine cycles before the flow of oil is fully established, and during this time, many parts are not properly lubricated. Adding to the problem is the fact that often the oil is cold at engine startup. Cold oil has much higher viscosity, which further delays proper circulation. A few engines have oil preheaters which electrically heat the oil before startup. Some engines have pre-oilers that heat and circulate the oil before engine startup. An electric pump lubricates all components by distributing oil throughout the engine. It is recommended that turbocharged engines be allowed to idle for a few seconds before they are turned off. This is because of the very high speeds at which the turbocharger operates. When the engine is turned off, oil circulation stops and lubricated surfaces begin to lose oil. Stopping the oil supply to a turbocharger operating at high speed invites poor lubrication and high wear. To minimize this problem, the engine and turbocharger should be allowed to return to low speed (idle) before the lubrication supply is stopped. Lubrication system in 2-stroke engines: Many small engines and some experimental two-stroke cycle automobile engines use the crankcase as a compressor for the inlet air. Automobile engines which do this generally have the crankcase divided into several compartments, with each cylinder having its own separate compressor. These engines cannot use the crankcase as an oil sump, and an alternate method must be used to lubricate the crankshaft and other components in the crankcase. In these engines, oil is carried into the engine with the inlet air in much the same way as the fuel. When the fuel is added to the inlet air, usually with a carburetor, oil particles as well as fuel particles are distributed into the flow. The air flow then enters the crankcase, where it is compressed. Oil particles carried with the air lubricate the surfaces they come in contact with, first in the crankcase and then in the intake runner and cylinder. In some systems (model airplane engines, marine outboard motors, etc.), the oil is premixed with the fuel in the fuel tank. In other engines (automobiles, some golf carts, etc.), there is a separate oil reservoir that feeds a metered flow of oil into the fuel supply line or directly into the inlet air flow. Fuel-to-oil ratio ranges from 30:1 to 400:1, depending on the engine. Some modern high-performance engines have controls which regulate the fuel-oil ratio, depending on engine speed and load. Under conditions of high oil input, oil sometimes condenses in the crankcase. Up to 30% of the oil is recirculated from the crankcase in some automobile engines. It is desirable to get at least 3000 miles per liter of oil used. Most small lower cost engines have a single average oil input setting. If too much oil is supplied, deposits form on the combustion chamber walls and valves will stick (if there are valves). If too little oil is supplied, excess wear will occur and the piston can freez e in the cylinder. Engines that add oil to the inlet fuel obviously are designed to use up oil during operation. This oil also contributes to HC emissions in the exhaust due to valve overlap and poor combustion of the oil vapor in the cylinders. New oils that also burn better as fuel are being developed for two-stroke cycle engines. Some two-stroke cycle automobile engines and other medium- and large-size engines use an external supercharger to compress inlet air. These engines use pressurized/ splash lubrication systems similar to those on four-stroke cycle engines with the crankcase also serving as the oil sump. Lubricating Oil: The oil used in an engine must serve as a lubricant, a coolant, and a vehicle for removing impurities. It must be able to withstand high temperatures without breaking down and must have a long working life. The development trend in engines is toward higher operating temperatures, higher speeds, closer tolerances, and smaller oil sump capacity. All of these require improved oils compared to those used just a few years ago. Certainly, the technology of the oil industry has to continue to improve along with the technology growth of engines and fuel. Early engines and other mechanical systems were often designed to use up the lubricating oil as it was used, requiring a continuous input of fresh oil. The used oil was either burned up in the combustion chamber or allowed to fall to the ground. Just a couple of decades back, the tolerances between pistons and cylinder walls was such that engines burned some oil that seeped past the pistons from the crankcase. This required a periodic need t o add oil and a frequent oil change due to blowby contamination of the remaining oil. HC levels in the exhaust were high because of the oil in the combustion chamber. Modern engines run hotter, have closer tolerances which keep oil consumption down, and have smaller oil sumps due to space limitations. They generate more power with smaller engines by running faster and with higher compression ratios. This means higher forces and a greater need for good lubrication. At the same time, many manufacturers now suggest changing the oil every 6000 miles. Not only must the oil last longer under much more severe conditions, but new oil is not added between oil changes. Engines of the past that consumed some oil required periodic makeup oil to be added. This makeup oil mixed with the remaining used oil and improved the overall lubrication properties within the engine. The oils in modern engines must operate over an extreme temperature range. They must lubricate properly from the starting temperature of a cold engine to beyond the extreme steady-state temperatures that occur within the engine cylinders. They must not oxidize on the combustion chamber walls or at other hot spots such as the center crown of the piston or at the top piston ring. Oil should adhere to surfaces so that they always lubricate and provide a protective covering against corrosion. This is often called oiliness. Oil should have high film strength to assure no metal-to-metal contact even under extreme loads. Oils should be non-toxic and non-explosive. Some desired qualities of Lubrication oil: Lubricating oil must satisfy the following needs: Lubrication. It must reduce friction and wear within the engine. It improves efficiency by reducing the friction forces between moving parts. Coolant Removal of contaminants Enhancement of ring seal and reduction of blowby Slow corrosion Stability over a large temperature range Long life span Low cost Hydrocarbon Components in Lubricating oil: The basic ingredients in most lubricating oils are hydrocarbon components made from crude oil. These are larger molecular weight species obtained from the distillation process. Additives: Various other components are added to create a lubricant that will allow for the maximum performance and life span of the engine. These additives include: Antifoam agents: These reduce the foaming that would result when the crankshaft and other components rotate at high speed in the crankcase oil sump. Oxidation inhibitors: Oxygen is trapped in the oil when foaming occurs, and this leads to possible oxidation of engine components. One such additive is zinc dithiophosphate Pour-point depressant Antirust agents Detergents: These are made from organic salts and metallic salts. They help keep deposits and impurities in suspension and stop reactions that form varnish and other surface deposits. They help neutralize acid formed from sulfur in the fuel. Anti-wear agents Friction reducers Viscosity index improvers Rating of Lubricating Oils and grades: Lubricating oils are generally rated using a viscosity scale established by the Society of Automotive Engineering (SAE). The higher the viscosity value, the greater is the force needed to move adjacent surfaces or to pump oil through a passage. Viscosity is highly dependent on temperature, increasing with decreasing temperature. In the temperature range of engine operation, the dynamic viscosity of the oil can change by more than an order of magnitude. Oil viscosity also changes with shear, decreasing with increasing shear. Shear rates within an engine range from very low values to extremely high values in the bearings and between piston and cylinder walls. The change of viscosity over these extremes can be several orders of magnitude. Common viscosity grades used in engines are: SAE 5 SAE 10 SAE 20 SAE 30 SAE 40 SAE 45 SAE 50 Common oils available include: SAE 5W-20 SAE 10W-40 SAE 5W-30 SAE 10W-50 SAE 5W-40 SAE 15W-40 SAE 5W-50 SAE 15W-50 SAE 10W-30 SAE 20W-50 Synthetic Oils: A number of synthetically made oils are available that give better performance than those made from crude oil. They are better at reducing friction and engine wear, have good detergency properties which keep the engine cleaner, offer less resistance for moving parts, and require less pumping power for distribution. With good thermal properties, they provide better engine cooling and less variation in viscosity. Because of this, they contribute to better cold-weather starting and can reduce fuel consumption by as much as 15%. These oils cost several times as much as those made from crude oil. However, they can be used longer in an engine, with 24,000 km (15,000 miles) being the oil change period suggested by most manufacturers. Available on the market are various oil additives and special oils that can be added in small quantities to standard oils in the engine. These claim, with some justification, to improve the viscous and wear resistance properties of normal oils. One major improvement that some of them provide is that they stick to metal surfaces and do not drain off when the engine is stopped, as most standard oils do. The surfaces are thus lubricated immediately when the engine is next started. With standard oils it takes several engine rotations before proper lubrication occurs, a major source of wear. Oil filters: Included in most pressurized oil systems is a filtration system to remove impurities from the engine oil. One of the duties of engine oil is to clean the engine by carrying contaminant impurities in suspension as it circulates. As the oil passes through filters that are part of the flow passage system these impurities are removed, cleaning the oil and allowing it to be used for a greater length of time. Contaminants get into an engine in the incoming air or fuel or can be generated within the combustion chamber when other than ideal stoichiometric combustion occurs. Dust and other impurities are carried by the incoming air. Some, but not all, of these are removed by an air filter. Fuels have trace amounts of impurities like sulfur, which create contaminants during the combustion process. Even pure fuel components form some contaminants, like solid carbon in some engines under some conditions. Many engine impurities are carried away with the engine exhaust, but some get into the interior of the engine, mainly in the blowby process. During blowby, fuel, air, and combustion products are forced past the pistons into the crankcase, where they mix with the engine oil. Some of the water vapor in the exhaust products condenses in the crankcase, and the resulting liquid water adds to the contaminants. The gases of blowby pass through the crankcase and are routed back into the air intake. Ideally, most of the contaminants are trapped in the oil, which then contains dust, carbon, fuel particles, sulfur, water droplets, and many other impurities. If these were not filtered out of the oil, they would be spread throughout the engine by the oil distribution system. Also, the oil would quickly become dirty and lose its lubricating properties, resulting in greater engine wear. Figure . Oil Filter Flow passages in a filter are not all the same size but usually exist in a normal bell-shaped size distribution. This means that most larger particles will be filtered out as the oil passes through the filter, but a few as large as the largest passages will get through. The choice of filter pore size is a compromise. Better filtration will be obtained with smaller filter pores, but this requires a much greater flow pressure to push the oil through the filter. This also results in the filter becoming clogged quicker and requiring earlier filter cartridge change. Some filter materials and/or material of too small a pore size can even remove some additives from the oil. Filters are made from cotton, paper, cellulose, and a number of different synthetic materials. Filters are usually located just downstream from the oil pump exit. As a filter is used, it slowly becomes saturated with trapped impurities. As these impurities fill the filter pores, a greater pressure differential is needed to keep the same flow rate. When this needed pressure differential gets too high, the oil pump limit is reached and oil flow through the engine is slowed. The filter cartridge should be replaced before this happens. Figure . Exploded view of an Oil Filter Figure . Pore size distribution for common filters Sometimes, when the pressure differential across a filter gets high enough, the cartridge structure will collapse and a hole will develop through the cartridge wall. Most of the oil pumped through the filter will then follow the path of least resistance and flow through the hole. This short circuit will reduce the pressure drop across the filter, but the oil does not get filtered. There are several ways in which the oil circulation system can be filtered: 1. Full-flow oil filtration. All oil flows through the filter. The filter pore size must be fairly large to avoid extreme pressures in the resulting large flow rate. This results in some larger impurities in the oil. 2. Bypass oil filtration. Only part of the oil leaving the pump flows through the filter, the rest bypassing it without being filtered. This system allows the use of a much finer filter, but only a percentage of the oil gets filtered during each circulation loop. 3. Combination. Some systems use a combination of full-flow and bypass. All the oil first flows through a filter with large pores and then some of it flows through a second filter with small pores. 4. Shunt filtration. This is a system using a full-flow filter and a bypass valve. All oil at first flows through the filter. As the filter cartridge dirties with age, the pressure differential across it needed to keep the oil flowing increases. When this pressure differential gets above a predetermined value, the bypass valve opens and the oil flows around the filter. The filter cartridge must then be replaced before filtering will again occur. Solid lubricants, such as powd

Charpy Impact Test Of Polypropylene At Various Temperatures

Charpy Impact Test Of Polypropylene At Various Temperatures This experiment examined the impact of polypropylene at various temperatures through the Charpy test. Three different forms of specimens including unnotched ones, blunt-notched and sharp-notched were tested to measure the impact energy. Results showed that low temperature resulted in the decrease of impact energy. These results have important implications for human designed applications concerning the toughness of polymers at different temperatures. The study of impact test has become an important aspect of toughness. Some progress has been made to understanding the mechanical characteristics of various polymers, especially toughness. Toughness, ability of a material to absorb energy and deform plastically before fracturing [1], is a concept most people have been accepted. It can be calculated by the areas under a stress-strain curve. Impact test, which describes the response of materials to a sudden high-speed force, can be divided into two different methods. One test method uses an instrument where a pendulum of known energy strikes a sample of defined size and shape. The other one test way uses an instrument where weights or others are allowed to fall freely through known heights on to specimens. [2] The first method mentioned above can be also separated from two kinds, which involve in cantilever (Izod) test and supported beam (Charpy) test. The illustrations of two tests are shown in Fig. 1.The distinct difference between the two methods is the fact that a specimen tested in the Izod is fixed in the horizontal direction instead of vertical direction tested in the Charpy. Fig.1 Izod and Charpy Impact Test (b) Charpy (a) Izod Temperature has an obvious influence in the behavior of polymers, such as tensile strength, shear stress, toughness, etc, because temperature affects the micro-structure of polymers. Among the changes, the inherent toughness is definitely dependent on temperature, structural orientation, stress concentration effects and rate of loading [3]. However, there have been few published reports directly addressing the problem of the effect on polypropylene at various temperatures. This experiment was to make clear of the relationship between the impact strength of polypropylene and temperature referenced in Charpy test. Experimental Equipment The equipment photograph is shown in Fig. 2 and the parameters of it are figured out in Table 1. Fig.2 Charpy impact test system Location: S.2.10 Table 1. Parametres of Charpy Impact Test Equipment Hammer Velocity Hammer Weight Hammer standard 2.9m/s 1.189kg ISO 2. Specimens A number of different rectangular-section standard polypropylene (PP) Charpy test samples including sharp notched, blunt notched and unnotched ones were tested at different temperature conditions. The different specimens are shown in Table 2. which also involves in the sizes (width and thickness) of the testing specimens. à ¢Ã¢â‚¬ ¦Ã‚  ,à ¢Ã¢â‚¬ ¦Ã‚ ¡,and à ¢Ã¢â‚¬ ¦Ã‚ ¢ in Table 2 are the four different dimensions separately. Table 2 Parameters of the specimens Room temperature Experimental Procedures: The specimens are divided into two parts, and one of the parts was put into the freezer before being tested. All of the data of an unnotched specimen at room temperature were input into the via keypad, and the sample was held onto the proper position of the equipment. A pendulum was raised to a specified height and then released when the equipment was started. Then the specimen was separated by the high-velocity pendulum. The impact energy was recorded in the Charpy impact test equipment. Steps 2 to 4 were repeated for each of the unnotched specimens to achieve a series of data. Steps 2 to 5 were repeated for all of the blunt-notched samples and then the sharp-notched samples. Steps 2 to 6 were repeated for the unnotched, the blunt-notched and the sharp-notched at -20à ¢Ã¢â‚¬Å¾Ã†â€™. Results and Discussion 1. Tabulate the individual values and average value of impact energy absorbed by the specimens for each test temperature. The individual data and average values of impact energy absorbed by the specimens for both two temperatures are listed in the two tables below. Table 3 illustrates the data at room temperature, and Table 4 exhibits the data at -20à ¢Ã¢â‚¬Å¾Ã†â€™. 2. Discuss the effect of temperature on impact energy for sharp notched, blunt notched and unnotched samples. Since the impact strength is dependent on the energy absorbed, a structure that is much easier to move will respond better to the impact [4].Therefore, the impact strength will increase with the increase of temperature and rubbery state has higher impact strength than glassy state. The higher the temperature is, the more severely the molecular chains will move. As a result, the impact energy is significantly lower at -20à ¢Ã¢â‚¬Å¾Ã†â€™ than that at room temperature. It can also be found in Table 4. 3. Analyze experimental error (a) When the parameters of specimens were measured, the apparatus error of vernier calipers could not be avoided. At the same time, the location of specimens was changeable, which was an operation error existed. (b) The sharp-notched samples were cut artificially, thus the factitious errors could not be ignored. (c) For the low temperature test, the frozen specimens were moved from a freezer to atmosphere, which might lead to the rising of temperature. As a result, the impact energy got a slight increase. (d) The errors of Charpy impact test equipment could not be ignored. Movement in the clamp and energy imparted to broken fragments might be the factors of the remaining energy of the pendulum and therefore the impact energy increased. [5] 4. Explain the cause of the whitening observed in some of the fractured samples. All kinds of the samples are listed in the Fig.3. Fig.3 The tested samples Through the observing of all different kinds of specimens, whitening is the most obvious in the unnotched samples. Many reasons listed lead to this phenomenon. Stress-whitening crazing usually can be observed for thermoplastics at levels of stress that below those required for large scale yielding. [6]When there is a sudden load to the sample, fracture crazes will be developed. Most of the time, it occurs in amorphous, brittle polymers and generally consist of an open network of polymer fibrils between 10 and 40nm in diameter, interspersed by void of about 10-20nm. [6] Conclusions After the experiment completed, many benefits of toughness and impact test have been listed below. There is a large variety of methods to measure impact energy of polymers and the most common used test is the Charpy test. With the decrease of temperature, the impact energy of same shaped specimens has a significant decline. The whitening of polymers is easier to be observed in the unnotched samples than that in sharp-notched and blunt-notched.

Faulkners Condemnation of the South in Absalom, Absalom Essay

Faulkner's Condemnation of the South in Absalom, Absalom       William Faulkner came from an old, proud, and distinguished Mississippi family, which included a governor, a colonel in the Confederate army, and notable business pioneers.   Through his experiences from growing up in the old South, Faulkner has been able to express the values of the South through his characters. William Faulkner's Absalom, Absalom offers a strong condemnation of the mores and morals of the South.      Ã‚  Ã‚  Ã‚  Ã‚   Faulkner's strong condemnation of the values of the South emanates from the actual story of the Sutpen family whose history must be seen as connected to the history of the South (Bloom 74).   Quentin tells this story in response to a Northerner's question:   "What is the South like?"  Ã‚   As the novel progresses, Quentin is explaining the story of the Sutpen myth and revealing it to the reader.   Faulkner says that the duty of an author, as an artist, is to depict the human heart in conflict with itself.   This attitude is revealed in the conflicts that Henry Sutpen undergoes in Absalom, Absalom.      Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Thomas Sutpen is the son of a poor mountain farmer who founded the Sutpen estate.   Thomas Sutpen stands for all the great and noble qualities of the South, and at the same time represents the failure of the South by rejecting the past and committing the same types of acts that his ancestors did (Connelly 34).   He rejects his own father to adopt a plantation owner as his surrogate father, who acts as a model of what a man is supposed to be.   When the plantation owner tells Sutpen to use the back door instead of the front door, Faulkner is using ... ...).    Works Cited    Aswell, Duncan. "The Puzzling Design of Absalom, Absalom!" Muhlenfeld 93-108    Bloom, Harold, ed.  Ã‚   Absalom, Absalom! Modern Critical Interpretations.   New York: Chelsea.  Ã‚  Ã‚   1987.    Connelly, Don.   "The History and Truth in Absalom, Absalom!" Northwestern University, 1991.    Faulkner, William.   Absalom, Absalom!   New York: Vintage, 1972    Levins, Lynn.   "The Four Narrative Perspectives in Absalom, Absalom!"   Austin: U of Texas,   1971.    Muhlenfeld, Elizabeth, ed. William Faulkner's Absalom, Absalom!: A Critical Casebook. New York: Garland, 1984.    Rollyson, Carl. "The Re-creation of the Past in Absalom, Absalom!"   Mississippi Quarterly 29 (1976): 361-74    Searle Leroy. "Opening the Door: Truth in Faulkner's Absalom, Absalom!" Unpublished essay. N.d.

A Womans Awakening :: essays research papers

The novel The Awakening by Kate Chopin tells the story of a woman who is married and has an awaking of her true feelings. The situation is very complex and Edna cannot handle the complexity of it. In the end she commits suicide. The novel The Awakening by Edna is described as a woman who is strong and able to persue her dreams. The novel also shows how people should live their lives for themselves instead of other people. Chopin uses characterization and symbolism to develop the meaning of the novel The Awakening. Ethan From is seen as a tragic person. He dreams of escaping his farm and living a life outside of Starkfield. Ethan was forced to leave college to care for his aging and ailing parents. He married Zeena because he feared loneliness and felt he owed her something for her help with his parents. Ethans character is described in the beginning of the novel as a man in his fifties, disabled, silent, and a farmer. Physically Ehtan is tall and bent-looking. His circumstances have made him weak. Ethan is a man of bad luck who is in his current situation due to circumstances and not by choice.   Ã‚  Ã‚  Ã‚  Ã‚   Edith Wharton portrays the land in Starkfield as harsh, the people are hard and unfriendly, and poverty as a mean way of life.She uses the landscape to reflect the personality of the characters. Her choice of winter is a symbol of the barrenness of the characters' lives. They are cold and isolated, like the temperature outside. The situations and conflicts are represented by Frome's stony landscape, the old apple trees, and the graveyard. In conclusion, Kate Chopin uses characterization and symbolism to develop the meaning of the novel The Awakening.

Socialism: What is the Ideal?

As a Salesman myself, I feel that I can relate to Death of a Salesman, to the extent of understanding what the job entails. In this essay, I shall depict the effects that socialism had on the characters of Death of a Salesman. I will include the social struggle of society, the contradictions involved, and the ideas of success, the character’s goals, and Willy’s downfall. I shall also include how Socialism has affected the real world and our nation’s society. Willy Loman’s world enticed him to become something he was not. Society placed a burden upon Willy’s head, of which he could not bare. But he was agonized by his awareness of being in a false position, so constantly haunted by the hollowness of all he had placed his faith in, so aware, in short, that he must somehow be filled in his spirit or fly apart, that he staked his very life on the ultimate assertion† (Miller 1594). Miller’s statement implies that Willy was in such a rut, knowing that he could not afford to pay for his appliances or even for his automobile, that he risked everything to succeed. The government however, in Willy’s world, defined what succeeding really is. Socialism means the substitution of governmental judgment for that of the individual and for individual ambition as well† (Myers 3). Willy’s ambitions involved obtaining a new career closer to his family and being able to afford all of his material objects. â€Å"Committed himself so completely to the counterfeits of dignity and the fake coinage embodied in his idea of success that he can prove his existence only by bestowing ‘power’ on his posterity, a power deriving from the sale of his last asset, himself† (Miller 1594). It is clear that the government played a major role in creating those ambitions. Biff’s social struggle included living up to his father’s expectations, of which his father did not necessarily approve of, until the end of the playwright. The government as a whole decided what was acceptable in society, and what was not, which is true to this day. Society has demanded a great deal from its inhabitants for thousands of years, especially in the United States. We soak up the governments and large corporation’s idealism everyday through nearly every source of entertainment we consume. A good example of true socialism would be a class-system, such as in central Asia, specifically China and India. For many years the Chinese and Indians have accepted a socialistic way of life, judging and ranking their citizens merely by blood-line and skin-color. For instance, both countries considered lighter (paler) skinned individuals as having a higher status compared to darker-skinned individuals. Therefore, even today, the sales of large amounts of skin-lightening creams exist in the Asian market. The largest contradiction I have come to understand is that exerting too much effort into an ideal ultimately ends in disaster. We witness this by examining Willy Loman. He, as a salesman, has an extremely stressful lifestyle. He ponders as to what he will do about his son Biff, and how he will be able to afford his bills. His lust for existence drove him mad, and eventually became the exact thing that invoked his demise. The ideas of success vary between characters in Death of a Salesman. Happy understood success as being able to provide for his family, more than merely financially. He always made statements on how him and Biff would open a sporting goods store, and be successful. Willy’s idea of success, in my opinion, was confirming his existence in society as a hard-working, honorable American. He however, drove himself mad as life-events spiraled downwards. Biff pursued to do something with his life, making his father happy in the process. Biff provides evidence of struggle by suggesting â€Å"When all you really desire is to be outdoors, with your shirt off. And always to have to get ahead of the next fella. And still – that’s how you build a future† (Miller 1429). That statement defines a key point in the story, because it symbolizes how each character yearns to get ahead and be successful. Miller’s playwrights were heavily influenced with Socialism, as Helge Nilsen states, â€Å"Human beings are sacrificed to economic interests in ways that are not only immoral, but even criminal in nature† (1608). That statement suggests that Miller purposely set each character up, in order to have a certain Socialistic ideal embodied within their personalities. Biff, however, has begun to rebel against his father’s ideas and to feel his way towards different standards, meaning those that Miller associates with the socialist society† (Nilsen 1609). The value of success is very difficult to measure. Each and every individual has their own understanding of success, as did Biff, Happy, and Willy. Society, for the most part, has labeled success as obtaining financial well-being. If someone were to be well off financially, then they are considered successful to the majority. Socialism has embedded that concept in our minds, from childhood to the present day. The socialist mentality is usually also an atheistic mentality, where atheism is understood not so much as the disbelief in God as the hatred of God – an attitude as precarious logically as it has been destructive in practice† (Kimball 16). That statement indicates that Socialism is equivalent to brainwashing an individual’s values. Willy’s goal in life, in my opinion, was to be successful enough to instill the correct ideals in his children’s mind, and to also recognize his own existence. Biff’s situation, in Willy’s mind, was a major conflict in his life. Without Biff becoming successful and making something out of his life, Willy would not exist and live up to his own ideals. Biff’s goals however, were filled with confusion and insecurity. Biff exclaims, â€Å"I’ve always made a point of not wasting my life, and every time I come back here I know that all I’ve done is waste my life† (Miller 1429). From that statement, I presume that Biff would like to fulfill his father’s request of not wasting his life. We witness that towards the end of the playwright, when Biff begins to sob and then embraces Willy. That moment in the play contributes a large amount to the irony towards the moral of the play, to exist is to meet one’s ideals. Willy’s realization however, brought upon his demise. Death of a Salesman’s overall plot and theme brings out a powerful message to today’s society. In our country today, individuals do not necessarily seek certain prospects out of pure joy, but rather out of financial greed. For example, class-systems still exist to this day in some countries, and diminish the value of overall life for the less fortunate. The ultimate downfall of Willy was that he consumed himself of his true values. His urge to make money and be a great salesman drove him wild. He did not realize what Biff was attempting to do until it was too late. As Nilsen stated, â€Å"But Biff continues his attempt to break through to his father’s feelings and establish a genuine connection and respect between them. Hence his plaintive cry: ‘Pop, I’m nothing†¦I’m just what I am, that’s all’† (1611). Since Biff did not abide by the socialist ideals of the time, Willy was determined to correct it. I believe Willy could not handle the pressures of life, and therefore ended up where he did. In this essay I have written about the effects of Socialism on the characters of Death of a Salesman. I described the effects social struggle, contradiction, ideas on success, their goals and Willy’s ultimate downfall. Writing on this topic was quite interesting, because it made me open my eyes on the current situations of our nation. Overall I believe Socialism is expressed greatly in this playwright, and that it teaches the reader that certain ideals such as financial prosperity are not always the answer to life.

Basic Concepts in the Law of Contracts

LGST 612 Prof. Kevin Werbach BASIC CONCEPTS IN THE LAW OF CONTRACTS Contracts are essential to business. They are a legal mechanism used in every industry and every part of the world to structure relationships among firms, and with customers, partners, and suppliers. Over several centuries, the law governing contracts has developed a large number of doctrines. Most are consistent with common sense, but unless you know what the rules are, you can easily make a mistake. This document introduces the fundamentals of contract law most relevant to businesspeople.Important legal terms are italicized. What is a Contract? And what is Contract Law? Legally, a contract is a set of promises that the law will enforce. We make promises all the time. Only some of them – the ones that meet the contract formation requirements listed below – are legally enforceable. That means the legal system, in the form of courts, can step in to order some action or payment for violation of the contra ct. Contracts are therefore private deals with the possibility of public (governmental) enforcement.Of course, there are many reasons to fulfill promises other than legal obligations. Reneging on promises may be unethical, or may result in a loss of goodwill or reputation as costly or more so than anything a court can impose. The general principles of contract law are fairly universal around the world. However, specific rules vary from country to country. In common law countries such as the United States and Great Britain, most of the legal doctrines governing contracts have been developed by courts over the centuries.In civil law countries such as those in Continental Europe, most of the terms of contract law are specified through comprehensive legislative codes. Even in the U. S. , some aspects of contract law are regulated by legislation. Certain classes of contracts involving employment, securities transactions, health care, and consumer financial transactions are subject to reg ulations that supersede the general principles of common law. Commercial contracts for the sale of goods (as opposed to services like consulting) are covered in virtually every state in the U. S. y the Uniform Commercial Code, which imposes specific statutory requirements. And certain contracts are made unenforceable by the Constitution: for example, a provision that a house may not be sold to a certain racial or ethnic group. Parties negotiating a contract each believe they will benefit from the agreement. For example, a corporation purchasing a license for enterprise software believes the benefit from the software will exceed the price it pays, and the software vendor believes the price will exceed sum of expected costs for providing access to its product.When parties enter into a contract, therefore, they generally do not expect it to be breached (violated), or to resort to the legal system. However, they recognize that sometimes a partner may make a promise with good intentions, and later fail to fulfill it, or that circumstances may chance in some way. When evaluating contracts, courts will generally not consider whether the deal was a good one for either side. The standard view is that no one forced the parties to enter into the contract; they should be held to the bargain they struck.Another way to think of a contract is as a legal hedge against uncertainty or risk. The contract gives each party confidence that if the other fails to perform, they can receive compensation through the courts. It also allows parties to specify how specific situations in the future may be addressed. For example, in the software license described above, what happens if the buyer decides to modify some of the software code and resell it? Rather than wait for the confusion if that happens, the parties can specify ahead of time how the situation will be handled, by adding provisions to the contract.LGST 612 (Prof. Werbach) Page 2 Contemporary legal systems focus on two things i n contracts cases: intent and reliance. If the evidence shows that all parties acted as though they intended to be legally bound to a contract, and the plaintiff (the one filing the lawsuit) reasonably relied on the defendant to follow through with the contract, the courts will generally enforce it. To do otherwise would be unfair to the party that was harmed by honoring their commitments. In modern contract law, intent and reasonable reliance often trump formalities.A contract may generally be enforced even if it not signed, written, or even expressly made. For example, if a fishmonger delivers fresh fish to a restaurant every Monday for a year and receives the same payment each time, there may be an implied contract even if the parties never explicitly spoke about it. The plaintiff still needs to convince the judge or jury in court, which is much harder to do based on oral testimony than documentary evidence. Unwritten contracts also leave significant gaps for courts to fill in.Th e implied contract between the restaurant and the fishmonger, for example, could be terminated at any time by the parties, because there is no explicit term guaranteeing how long it will last. Remedies What a court awards to a successful plaintiff for breach of contract is known as the remedy. In contract law, the sole purpose of the remedy is to adequately compensate for the breach. You cannot receive additional â€Å"punitive† damages to punish someone for breach of contract, as you might under a tort claim such as products liability. The same facts, however, might give rise to both kinds of claims, as when a party deliberately breaks a contract in order to harm the other party’s business. ) In most contracts cases, the remedy is a payment of money, known as damages. There are three main ways that courts may calculate the level of damages: †¢ Expectation is the preferred formula. Whenever possible, this is what courts will use. Expectation means that the plainti ff (who did not breach the contract) gets the â€Å"benefit of the bargain. † In other words, they receive compensation to put them in the position they would have been in, had the contract been performed.For example, if an airline enters into a futures contract to purchase jet fuel in one year at $4/gallon, and at the time of performance the fuel company breaches because the spot market price is now $7/gallon, the expectation remedy would be $3/gallon times the number of gallons. In other words, it is the difference between the market and contract price. That way, the airline can buy the fuel from someone else at the market price, and still get the benefit of the contract. Reliance is used when expectation damages cannot be calculated because the amounts are too uncertain, or there is some other reason not to give expectation damages.Under this formula, the plaintiff gets back any costs he or she has expected by relying on the contract, so they are no worse off than before t he agreement. Generally, this will be a smaller amount than the expectation remedy. Restitution is used in rare situations where even reliance damages are not feasible to determine. Under this formula, the defendant (who breached the contract) must give back whatever benefit he or she received from the plaintiff, even if this does not fully cover the plaintiff’s reliance.For example, if the plaintiff paid money to the defendant for some services, the defendant must give it back. †¢ †¢ Courts may also consider awarding incidental and consequential damages. These are other costs the plaintiff can demonstrate, which go beyond his or her expectation under the contract. For example, imagine a factory owner contracts for a $50,000 piece of machinery to power a production line, and LGST 612 (Prof. Werbach) Page 3 the supplier breaches the contract. It takes a month before the factory can obtain an equivalent machine from another supplier (also for $50,000).As a result, the factory loses one month of production, which produces financial losses of $500,000 and causes its customers to terminate future orders worth several million dollars. All those costs are considered consequential damages. Whether they can be recovered depends on how foreseeable they were, and on the terms of the contract itself. On the one hand, those are actual losses the plaintiff suffered; on the other hand, was it reasonable to think the defendant took on millions of dollars of potential liability when it sold a $50,000 machine?In limited situations, monetary damages are not sufficient to give the plaintiff an adequate remedy. In such cases, a court may order an injunction (forbidding the defendant from some course of action) or specific performance (affirmatively ordering the defendant to go through with the transaction). Specific performance is only available for unique objects, where the money to purchase a similar object is not considered sufficient. This includes things such as works of art and real estate. Breach Failing to follow through on the legal obligations of a contract is called a breach.A breach might mean one party totally ignored its contractual obligations, or that it failed to perform some of them (such as completing the contracted-for services within a specified time), or that it did so in an inadequate manner. Whether something constitutes a breach is a factual decision for the court. The decision may be easier if the contract itself specifies conditions for breach, or whether a failure to perform specific responsibilities constitutes a breach of the whole agreement.As mentioned above, breaching a contract is not the same thing as breaking a promise, because law and ethics are not identical. In particular, sometimes a breach is, economically at least, a good thing. Imagine that an architect contracts with a cabinetmaker for custom-designed built-in furniture in a renovated house. However, the owner of the house changes her mind before f inalizing her contract with the architect, and he loses the commission. The cabinetmaker has not yet started to manufacture the furniture.It would be wasteful to force the architect to go through with the contract, when he knows the cabinets will be useless. It is more efficient for the architect to breach the agreement. So long as the architect pays sufficient compensation to the cabinetmaker (voluntarily or in the form of monetary damages or a voluntary payment), there is nothing unethical in his breach. Contract Formation There are five required elements for a legally binding contract. In other words, a plaintiff suing for breach of contract must first show that all five were met. Then they must show the contract was breached, and they are entitled to a remedy. ) 1. 2. 3. 4. 5. Offer Acceptance Consideration Legality Capacity The first two requirements, offer and acceptance, are sometimes lumped together and called â€Å"mutual assent. † They are typically the most difficu lt and important elements to establish. LGST 612 (Prof. Werbach) Offer Page 4 An offer is a proposal that manifests intent to enter into a contract. It is distinguished from an invitation, which is merely a proposal to enter into negotiations and therefore not legally binding.The party that makes an offer is called the offeror and the party that receives it is called the offeree. For the offer to be valid, the offeror must: 1. Manifest the intent to enter into a contract 2. Be definite and certain regarding the essential terms of the proposed contract 3. Communicate the offer to the offeree Suppose you are at a used-car dealer's lot. You see a care you like with the price listed as $9,995. You ask the salesperson what he’d take for the car; he doesn't answer you, but responds by asking you what you would offer.If you then say, â€Å"I wouldn't pay the list price, but I might pay $8,000 if I could finance it,† have you made an offer? In considering questions of this typ e, courts will look to â€Å"objective† manifestations of intent. Would a reasonable (ordinary, average) person, listening to your conversation in context, think that you intended to bound into a contract if the salesperson accepted? Again, reasonable reliance is what the courts look to protect, so your subjective mental state, even if it could be reliably determined, is irrelevant. Courts do, however, consider the context.You might offer to purchase a candy bar simply by holding out a dollar bill to a cashier, but an offer to enter into a multi-million dollar merger agreement might require significantly greater formalities. Similarly, if it would be clear to a reasonable observer that a statement was made as a joke, or in a social setting that does not involve contractual obligations, such as a wedding invitation, there is no binding offer. All these, however, are factual questions that courts might assess by hearing witnesses, looking at evidence, and listening to experts.A cceptance An acceptance is the mirror of an offer. If the offeree (the one receiving the offer) objectively manifests intent to be bound, the other elements below are met, and the offer is still valid, a contract comes into being at that moment. Intent is evaluated the same way for acceptance as for the offer. For the acceptance, however, courts are more sensitive to situations where someone takes actions that indicate acceptance (such as signing a document), but does not in fact understand the obligations they are undertaking.In such cases, courts generally look to whether this is the sort of contract that is typically accepted in that manner, and whether the offeree had a reasonable opportunity to analyze the contract but chose not to. Many business-to-consumer agreements are so-called contracts of adhesion or form contracts, where the consumer has no real opportunity to negotiate the specific terms – think of a rental-car agreement – but acceptance is still generall y considered valid because there are other means to protect the consumers and the alternative would be extremely inefficient and cumbersome.There are four ways that an offer may no longer be valid: 1. The offeror may generally revoke the offer by communicating that to the other party at any moment before acceptance. 2. If the one receiving the offer rejects it, which includes making a counter-offer, the original offer is considered no longer binding. 3. After some reasonable period of time, determined by the court based on the context, offers lapse. You cannot walk into a used-car dealer and say you are accepting the list price of a car advertised two years before. 4. Death or incapacitation of an offeror generally cancels an offer.One exception to the rule about revocation of offers is the option contract. This is essentially a contract that binds only one party. For example, a property owner might grant a real estate investor LGST 612 (Prof. Werbach) Page 5 an option to purchase a building for $15 million within a period of 90 days. If the investor comes forward with the $15 million, the owner must sell the building. The investor, however, is under no obligation to do anything. (Options on stocks operate the same way; the price for the put or call is the payment for the option. ) Under U. S. aw, there must be a separate payment for holding open the option, even if it is specified in the same document as the purchase terms. In other words, in the real estate example, if the building owner promised to keep the offer open for 90 days, but received no compensation for that promise, it would technically be free to sell to someone else. In many other countries, a party that promises an option must keep it open for a reasonable period of time, even without payment. The acceptance must mirror the offer. That means the offeree must comply with any conditions the offeror placed on the offer.If, for example, the offer states that payment must be made in cash, or that t hose wishing to accept the offer must show up in person at a certain location, those conditions must be met for a valid acceptance. If the offeror does not specify, the offeree may use any reasonable means. This may even include actions rather than words. If I ask a friend to bring me a sandwich from the cafe downstairs, which I’ll pay for, and she immediately goes to purchase it without saying a word, her actions would likely be a sufficient manifestation of intent.As always, context matters. In a complex commercial negotiation, it may be reasonable to exchange numerous very specific drafts, which are not formally accepted until the final version is signed off on by senior executives. Consideration Consideration means that each party has committed to giving up something of value to induce the promise or action of the other party. It is the way the law distinguishes an enforceable contractual bargain from a gift. If someone promises to give you a gift, and then reneges on the promise, you cannot sue them for breach of contract.There was no contract to begin with, because you did not have to give anything up in return for the gift. In most contracts, consideration will be money in exchange for some goods or services. However, it can be anything of legal value, including property or voluntarily giving up a legal right to act in a certain way. In a famous case, a court held that an uncle’s promise to pay money to his nephew if the nephew gave up smoking and drinking was enforceable, because the nephew stopped doing something he was legally entitled to do. The consideration must, however, be needed to induce the promise.If your action or inaction wasn’t what motivated the other party, there is no consideration. The amount of consideration need not match the value of what the party receives in return. A contract to pay $100 for a computer worth $1,000 may be a bad deal, but it has sufficient consideration. The main question is whether there is something of value exchanged to demonstrate the agreement is not a gift. In business agreements, this sometimes means a recital (a contractual provision that simply states a fact) along the lines of, â€Å"in exchange for good and valuable onsideration of one dollar†¦Ã¢â‚¬  to ensure consideration is found. Legality Contracts that are made for an illegal purpose will not be enforceable in a court of law. An agreement with a hit man to kill a disfavored relative may meet all of the formalities of a contract, but it should be obvious that you could not sue him for failing to go through with it. More realistically, an agreement to engage in bribery or to restrain market competition in violation of antitrust laws would be unenforceable.Capacity All parties to a contract must have the legal capacity to enter into a binding agreement. In other words, they must have what the law considers sufficient mental fortitude to understand and commit to LGST 612 (Prof. Werbach) Page 6 the obl igations involved. Two main classes of people who do not have capacity are children and those under significant mental disability or impairment. Children are generally not allowed to become legally bound by contracts. (The specific age cutoff and other considerations vary from jurisdiction to jurisdiction. If an adult contracts with a child, the child can void the contract at will, but the adult is still bound if the child wishes to enforce the agreement. The other situations in which capacity becomes an issue are when a party either has a significant disability that prevents them from understanding contractual obligations, or they are too severely impaired by drugs, alcohol, or another factor. Capacity is judged objectively: would a reasonable observer think the party was in a state that made it impossible to express intent to contract?If so, the party at that moment lacks the legal capacity. It is important to note that capacity is not the same thing as capability or authority. A bank may not actually have the financial wherewithal to provide the financing that it contracts for, but this does not mean it is incapable of entering into any contract. If it fails to provide the financing that the other party reasonably relied on, it is in breach of contract, whether or not it actually has the resources needed to perform. Similarly, an agent may or may not have the legal authority to speak for a firm.If a sales representative (or someone claiming to be a sales representative) commits a company to an agreement with a customer that the company does not in fact wish to honor, that has no bearing on the legal capacity to contract. In that situation, the court must determine whether it is appropriate to bind the company. If the salesperson did not in fact have actual authority to sign off on such contracts, courts would look to whether it was reasonable for the customer to think that they did, especially without communicating with corporate headquarters.Whether a Cont ract Must be in Writing (â€Å"Statute of Frauds†) As mentioned above, there is no general requirement that contracts be in writing. It is generally a good idea to write contracts down, because that provides clear evidence of their existence and terms if they are ever breached. Fundamentally, though, an oral agreement, or an unsigned written agreement, is a valid contract, except in two broad cases. The first is when there is a statutory or regulatory requirement to put a certain agreement in writing. This is often the case, for example, with financial and healthcare agreements.The second is if the contract is under the statute of frauds. The Statute of Frauds was a 17th century English law that required some contracts to be in writing, because otherwise there would be too much risk of witnesses lying (the â€Å"fraud†) in their oral testimony in court. Today, the term refers mostly to common law principles that impose a writing requirement, plus provisions of certain modern statutes (such as the Uniform Commercial Code) that impose similar obligations. Saying that a contract is â€Å"under the statute of frauds† means that it has to be in writing.There are several categories of contracts that fall under the statute of frauds, including suretyship (promising to pay someone else’s debts) and contracts in consideration of marriage (such as prenuptial agreements). The three categories most likely to arise in a business context are: †¢ †¢ Sale of land. This also includes interests in land, such as a mortgage. Sales of goods worth $500 or more. Note that contracts for services, such as consulting or financial advice, are not covered under this provision. The $500 figure comes from the Uniform Commercial Code, and is an arbitrary figure, not pegged to inflation.LGST 612 (Prof. Werbach) Page 7 †¢ Promises not performable in one year. In other words, there is no way the contract could be successfully performed within a year. If the contract does not specify a term of longer than a year, and there is come conceivable scenario in which both parties would discharge their responsibilities before the end of the year, it need not be in writing. If a contract falls under the statute of frauds, a sufficient â€Å"writing† is a document that identifies the parties, describes the basic obligations of the contract, and is signed by the party to be charged.As with any written contract, if there are specific details not set out in the document, the court can interpret the language or fill in reasonable terms as necessary to enforce it. If, however, the writing is missing a material term – for example, the price in most sales contracts – it is not enforceable. Basically, the court needs enough information to determine a remedy. If the contract is not under the statute of frauds, the courts can look to other written evidence or oral testimony to find a material term. However, if the parties simply failed to agree on such an essential point, the contract is unenforceable.Note that when the statute of frauds applies, only one party is required to sign the agreement: the party who is being sued to enforce it (the defendant). The signature of the other party may still be useful to prove there was intent to enter into a binding agreement. Excuses to Performance In some circumstances, a party will not be held to an agreement, even when it met all the legal requirements for a valid contract. The most common excuses to performance are: Fraud. If one party induces a contract by lying to the other party, it is not enforceable even when the form of the contract is perfectly good.Duress. If a party felt it was forced to enter into a contract against its will, it can claim the contract is unenforceable due to duress. This means something more than a difficult situation or a tough negotiating partner on the other side. For example, if there is only one supplier for an important input with sufficient production capacity, buying from that supplier is not duress. There must generally be some misconduct, involving threats to engage in illegal conduct or breach other obligations, which convinces the other party it has no choice. Unconscionability.As noted above, a contract will not be considered unenforceable because it is unfair, or because there is unequal bargaining power (as is typically the case in business-to-consumer interactions). However, if one party has no reasonable opportunity to understand the obligations they are undertaking, or there are terms in the agreement so manifestly unfair that they â€Å"shock the conscience,† courts can declare specific provisions or whole contracts as unconscionable. This doctrine is successfully invoked infrequently, and then typically when there is unfairness in the process, rather than the substantive terms.Mutual mistake. If both parties were mistaken about the fundamental subject matter of the contract, such that th ey never truly had an agreement, the contract can be declared unenforceable. If the mistake is simply a bad business decision, such as an assumption that the price of a good will not increase substantially, it will not excuse performance. Impossibility/frustration of purpose. If circumstances change so dramatically that either a contract is effectively impossible to perform, or it would be pointless to complete it, courts can excuse performance.As with the other doctrines, courts will not release parties from their obligations if performance is merely more difficult or costly than they expected. – – – – LGST 612 (Prof. Werbach) Page 8 These excuses are considered by courts after the fact. In such situations, there is a contract, but there is no legal remedy for a breach. Sometimes, the result is merely to sever a problematic provision of the contract. For example, a contract may be enforceable minus the specific term the court considered unconscionable.Re covery Outside of Contract (â€Å"Promissory Estoppel†) Modern contract law makes it relatively easy for parties to enter into contracts, to specify the terms of those contracts, and to be excused from contractual obligations when fundamental fairness dictates. Consequently, the legal system generally focuses on whether the procedural obligations of contract law described above have been met, rather than on whether the outcome is just. After all, the parties were free to act differently, yet chose to structure their agreement in a certain way.Why should the courts interfere with their decisions? In a host of cases, this freedom-based view of contracts fails to account for reality. Inequalities in access to information or bargaining power may so warp the relationship between parties that the formal structure of an agreement may not actually reflect the intent of at least one of them. Or there may be significant public policy concerns, such as avoiding mistreatment of patients or retail investors, which counsel for heightened obligations beyond those of common-law contract doctrines.Another category cuts in the opposite direction. Sometimes the un-enforceability of an agreement is unfair. If one party reasonably relies on the other party, yet has no remedy because the agreement is unenforceable, it can create a situation in which the courts view themselves as parties to an injustice. The legal doctrine known as promissory estoppel arose to allow for recovery of damages in court, even when there is no enforceable contract between the parties.The Restatement (Second) of Contracts, a collection of â€Å"best practices† in contract law written by leading legal experts in the field, describes promissory estoppel as follows: â€Å"A promise which the promisor should reasonably expect to induce action or forbearance on the part of the promisee or a third person and which does induce such action or forbearance is binding if injustice can be avoided only b y enforcement of the promise. The remedy granted for breach may be limited as justice requires. † Most commonly this doctrine is invoked for charitable gifts.For example, imagine that a donor to Wharton promises the school $100 million for a new building bearing her name, the school builds the building in reliance on the gift, and the donor then reneges on the promise. There is no enforceable contract, because there is no consideration. (The school’s expenditure in building the building was a response to the promised gift; it is not what induced the promise, as required for consideration. ) In such a situation, if a court feels it would be an â€Å"injustice† that Wharton receives no compensation, it can award damages on a promissory estoppel theory.Courts have applied promissory estoppel in other situations where, because of some legal quirk, a party reasonably relies on a contract and yet has no adequate remedy. Note that promissory estoppel is a distinct legal claim, not a lawsuit based on a valid contract. One consequence is that damages are generally limited to reliance. In the donation example in the previous paragraph, this means that Wharton might recover the amount it spent on constructing the building, but not the full $100 million that was promised. And remember that the court can decline to award anything if it does not feel that an injustice has occurred.