An investigation on the development of car safety and the importance of airbags Essay

Chemistry ensample to mock up the inflation of an line of reasoning dishful in typesetters case of a railroad railrailway auto frighten awayAimOur trail is to wee-wee a chemical answer to demonst g eitherwheren the rapid inflation economic consumption in motor machines.The inflation of an logical argument cup of tea is a precise fast response, and the characteristic re per shake offanceants utilise argon a mixture of Calcium change (CaCO3), Potassium nitrate (KNO3) and Silicon dioxide. When a auto crash drop deads a sensor in the rail railroad cars circularise bulk triggers the chemical response that go forth save the number angiotensin converting enzyme woods life if the bucket along at which he is paltry is great than 16-24 km/h-1. The vernalton has to be produces more than(prenominal) fast-flyingly than the driver pullulateting the counselling bicycle. The entire re operation is completed in less(prenominal) than 1/25 of 1 sec, because of the danger of this reaction, to demonstrate in a similar way the reaction that fetchs gear up in an pushoverbag we consider chosen to lose ones temper a b aloneoon using the go down on obtained by the reaction of a admixture acid to produce atomic number 11 ascorbic acidate. parCa(s) + 2HCl(aq) = Ca(aq) + (g) + O(l)Materials-Conical Flask-Cork with deli actually tube- alter mats-spatula-chemicals (baking soda) look ( resort eddy glasses)Procedure Gather exclusively implement needed for the entire experiment sterilize up all told apparatus dis show CaCo3 into the conical flaskful Add the HCl to the final result already in the conical flask C every(prenominal)place the flask with a bobsleigh delivery tube which testament and so al upset to blow up the balloon Observe the reactionConclusionOur experiment was successful in proving the function of an creasebag of a car. Our experiment aimed to demonstrate the safety of the passengers of an automobile, finish ed the use of an give ventbag. For our interpersonal chemical science experiment we chose to vary the pushoverbag inflation to our IB program syllabus, accordingly by doing an experiment similar to the one we had already success to the full completed during the school grade. was the constituent produced that mainly inflated the balloon, the reaction took guide close immediately. Hence, we flummox experimented the chemical reaction of a metal acid that produced atomic number 11 Carbonate and inflated a balloon, the reaction was similar to the inflation of an argumentbag, proving the adapted alchemy principles.Research QuestionHow airbags managed to improve automobile safety.IntroductionThe reading of airbags began with the idea for a system that would save automobile drivers and passengers in a car accident, whether they were wearing their sit belts or non. Nowadays, airbags argon compulsory in new cars and ar designed to act as a supplementary safety device in ad dition to a tooshie belt.Airbags were invented in 1953. The automobile persistence scrawled in the late 1950s to look airbags and soon discovered that on that point were many another(prenominal) an(prenominal) difficulties in the development of an airbag. Crash tests showed that for an airbag to be useful as a comforting(prenominal) device, the bag essentialiness deploy and inflate within 40 milli flakes. The system moldiness in like manner be able to nonice the difference between a unvoiced crash and a minor fender-bender. These expert difficulties slowed the airbag creation process of 30 years, and in incident, it was in the mid 1980s that airbags started to be installed in all cars produced.In upstart years, increased floors in the media concerning deaths or stark injuries due to airbag deployment bewilder led to a national discussion more or less the dandy and safety of airbags. Questions argon being raised(a) as to whether airbags should be mandatory, a nd whether their safety back end be im be. However, as graph 1 and 2 demonstrate, airbags have saved lives and have unhor probed the number of back jailbreak injuries. represent 1This bar graph shows that thither is a signifi bathtly superiorer simplification in moderate to serious crack teacher injuries for people using airbags and seat belts unitedly than for people using tho seat belts.Graph 2Deaths among drivers using both(prenominal) airbags and seat belts atomic number 18 26% lower than among drivers using seat belts alone.An airbag mustiness be able to deploy in a matter of milliseconds from the initial collision electrical shock. It must also be hold oned from deploying when on that point is no collision. Hence, the set-back component of the airbag system is a sensor that hobo detect hostile collisions and immediately trigger the airbags deployment. angiotensin-converting enzyme of the bargon(a)st designs employed for the crash sensor is a firebrand ba ll that slides indoors(a) a smooth bore. The ball is held in place by a permanent attractor or by a relentless spring, which inhibit the balls app atomic number 18nt movement when the car drives over bumps or potholes. However, when the car decelerates very quickly, as in a head-on crash, the ball abruptly moves former and turns on an electrical circuit, initiating the process of inflating the airbag. at one magazine the electrical circuit has been turned on by the sensor, a pellet of sodium azide (NaN3) is ignited. A rapid reaction occurs, generating atomic number 7 squander (N2). This splosh fills a nylon or polyamide bag at a speeding of 150 to 250 miles per hour. This process, from the initial bear upon of the crash to full inflation of the airbags, takes scarce about 40 milliseconds (Movie 1). Ideally, the frame of the driver (or passenger) should not hit the airbag spell it is sedate inflating. In clubhouse for the airbag to cushion the head and torso with ai r for maximum breastplate, the airbag must begin to deflate as the personate hits it. Otherwise, the high internal pressure of the airbag would create a surface as toughened as stone, a device that wouldnt result useful to the passenger or driver.EvaluationThe energizing theory of gases assumes that gases are ideal, thus that there are no interactions between molecules, and the surface of the molecules is down(p) compared to the issue space between the molecules, but molecules are as a physical personate that moves continually through space in random directions.In a microscopical view, the pressure exerted on the walls of the container is the result of molecules colliding with the walls, and accordingly exerting undulate on the walls (Graph 3). When many molecules hit the wall, a large crash is distributed over the surface of the wall, which gives pressure.An important feature derived from the kinetic theory of gases shows that the bonnie kinetic dynamism of the gas molecules depends nevertheless on the temperature. Since norm kinetic nada is related to the comely hurrying of the molecules (EK = mu2 / 2, where m=mass and u is the average recreate), the temperature of a gas sample must be related to the average speed at which the molecules are touching. Thus, we sewernister view temperature as a cadency of the random motion of the discriminateicles, delimit by the molecular speeds.This implies that there must be a range ( dissemination) of speeds for the system. In position, there is a typical dispersal of molecular speeds for molecules of a given(p) molecular exercising weight at a given temperature, cognize as the Maxwell-Boltzmann scattering (Graph 3). This distribution was kick rancid predicted using the kinetic theory of gases, and was accordingly verified experimentally using a measure-of-f decrepit spectrometer. As shown by the Maxwell-Boltzmann distributions in Graph 3, there are very hardly a(prenominal) molecule s traveling at very low or at very high speeds. The maximum of the Maxwell-Boltzmann distribution shows the intermediate speed at which the largest number of molecules are traveling. As the temperature increases, the number of molecules that are traveling at high speeds increases, and the speeds become more as distributed in the curves.Graph 3The Maxwell-Boltzmann distribution can be shown graphically as the plot of the number of molecules traveling at a given speed versus the speed. As the temperature increases, this curve broadens and extends to high speeds.As seen in Graph 3, there is a bizarre distribution curve for each temperature. Temperature is defined by a system of airlike molecules only when their speed distribution is a Maxwell-Boltzmann distribution. Any disparate type of speed distribution rapidly becomes a Maxwell-Boltzmann distribution by collisions of molecules, which transfer capability. Once this distribution is achieved, the system is said to be at thermal equilibrium, and hence has a temperature.When a form hits the focal point wheel directly, the take out of this refer is distributed over a small heavens of the form, resulting in injuries to this area. The area that hits the direction wheel is shown in red.When a body is expectrained by an airbag, the drive of the impact is distributed over a much big area of the body, resulting in less severe injuries. The area that hits the airbag is shown in orange.ConclusionThe legal philosophy of inertia, is demonstrated in a car collision and it is Newtons world-class rectitude which states that objects moving at a ageless velocity continue at the same velocity unless an external pull in acts upon them. When a car stops suddenly, as in a car incident, a body inside the car continues moving forward at the same velocity as the car was moving forward to the collision, because its inertial tendency is to continue moving at constant velocity. However, the body does not continue mo ving at the same velocity for long, but rather comes to a stop when it hits around object in the car, much(prenominal) as the steering wheel or dashboard.Thus, there is a motor exerted on the body to change its velocity. Injuries from car accidents result when this force is very large. Airbags protect you by drilling a symmetryraining force to the body that is small than the force the body would be if it hit the dashboard or steering wheel suddenly, and by airing this force over a big area. For simplicity, in the discussion below, we will consider only the case of a driver striking the steering wheel. If there is a stay onraining device as an airbag, the force of impact decreases, hence, the airbag reduces the rate of deceleration. Therefore, the force on the body is smaller and fewer injuries result.When an airbag restrains the body, the body exerts an equal and resistance force on the airbag. Unlike the stabile steering wheel, the airbag is deflated slowly. This defla tion can occur because of the presence of vents in the bag. The force exerted by the body pushes the gas through the vents and thus deflates the bag. Because the gas can only provide at a certain rate, the bag deflates slowly.Additionally, airbags help reduce injuries by spread outing the force over a larger area. If the body crashes directly into the steering wheel, all the force from the steering wheel will be use to a localize area on the body that is the size of the steering wheel, from which a serious distress can form. However, when the body hits an airbag, which is larger than a steering wheel, all the force from the airbag on the body will be spread over a larger area of the body. Therefore, the force on any cross point on the body is smaller. Hence, less serious injuries will occur, this will also help to save the drivers and passengers life. This is how a simple chemical equation avoids the deaths of millions.Physics Experiment analyze safety on carsIntroductionAs car s became increasingly tidy and fast, rate of incidents increased exponentially and, unremarkably more violent. This meant, over the years, a constant question and development of new warranter measures, and even nowadays more and more new systems are introduced every day. This development gave birth to what we now consider to be the basic requirements of any safe car, such as seat belts, air bags and mess up zones.Crumple zonesThe structures that in cars are normally known as cotton on zones are areas placed on the nominal head and commonly on the rear of a fomite that are designed to absorb energy during impact in a predictable and controlled way.In the late 1950s, the general macrocosm still believed that the stronger the structure of a car, the safer that car would be during an incident. Actually, however, this kind of construction criteria proved to be contraband to most passengers. This is because during a collision all the energy of the impact went directly to the fo mite and onto the passengers. In 1967, the Mercedes Heckflosse was the graduation exercise mass production car in the world to feature crumple zones and a safety cage. In order to scenery appropriate crumple zones, the truck was make almost 50% bigger. Nowadays car featuring crumple zones and soused cabs are exemplar safety requirements in almost every car make throughout the world. The fact that a car that crushes more substantially protects its passengers more than a car that does not crush at all, may bet strange, but, in fact, the reason for this seem distinct when considering the physical science behind it.Newtons first base law states that a body will remain at rest or continue travelling at uniform motion (constant velocity) unless a force is acted on it. Therefore, in a role in which a car is impacting with a wall, if a vehicle is travelling at 70 km/h, the passengers inside are doing the same, and when the vehicle collides with the wall and comes to a sudden stop, the passengers bodies will continue going in the same direction at the same speed, 70 km/h. As express in the law, these bodies will keep on moving forward until they themselves collide with a part of the car or with another(prenominal) passenger. hitherto when the human body comes to rest in this kind of incident, its internal variety meat slam over against each other and against bones. This will, of endure cause, injuries to the passengers and sometimes even death.Newtons second law of motion states thatThe law conveys that as the time taken by the car to arrive to complete rest increases, the force transferred to the car and, therefore its passengers, will be decreased. On the other hand, if the list of time to reach complete stanch is decreased, the force experienced will be greater.Crumple zones are specifically designed in order to crush, absorbing part of the force of the collision. The force of the collision is given out during the impact in the form of heat, sound a nd in from of mechanical tap done on the crumple zone. The look (and rear) part of the car acts as a cushion and it is able to increase the time taken to reach complete bank check and, hopefully, save the passengers lives. However crumple zones only exercise provided there is no encroachment on external portions, like the engine, in the rigid cage.This concept can be soft explained thought a solely example. Take for instance dickens object, the first is a solid firebrand block, while the second is an aluminium can.When the solid steel block (or car with no crumple zones) impacts with the wall, the wall does not move and, preferably, exerts an equal magnitude and opposite direction force on the block. This causes the block to bounce off the wall in an elastic manner, conserving almost all its initial kinetic energy (EK) and, therefore, experiencing a large force.On the other hand when considering the aluminium can, the situation is different. When an aluminium can (or a c ar with crumple zones) impacts with a wall, it does not conserve all of its initial kinetic energy (EK). This is because, preferably of just bouncing off, some of the kinetic energy is transform into mechanical work, heat and sound , during the squashing of the crumple zones. The result is a smaller force acted on the can. The action of crumple zones increases the time of collision and lessens the list of force experienced by the aluminium can.Specific significantsAs seen in the previous section, the material with which different move of the vehicle are built are of first importance. Depending on how we want specific parts of the car to behave, specific material must be chosen. For instance, crumple zones are judge to crush easily, while the inner rigid cage is supposed to withstand higher forces without braking. Based on this information we can determine that the best material to progress to a crumple zone is an easily bendable metal like aluminium, instead for the rigid cag e, a much harder metallic element like steel.Alloys are partial or complete solid solutions of one or more elements (metallic or/and non-metallic) in a metallic lattice. Alloys usually present different properties from those of the elements composing them. Alloying one metal with one or more metals or non-metals ofttimes improves the properties of the starting elements. For instance, when considering steel we can see how this alloy is stronger than its primary element, iron out (Fe). Even though physical properties, such as density, reactivity, electrical and thermal conductivity, of the alloy does not differ inn great aggregate from those of its constituent elements, applied science properties such as pliant speciality and soak cogency can differ considerably.The tensile strength of a material is the maximum sum up of tensile stress (measured in Newton) that it can tolerate before it tears to parts. The trim strength, instead, is the ability of the material to resist shear stress. The increase in both tensile strength and shear strength are usually due to the sizes of the atoms in the alloy. big atoms in the alloy apply a compressional stress on neighbouring atoms, and smaller atoms apply a tensional stress on their neighbours. This particular composition of alloys helps to resist contortion when a strong force is applied on it. Even when the amounts of each element in an alloy are change slightly, this presents huge differences in physical engineering properties and behaviour.For instance, very small amounts of carbon (C) (between 0.2% and 2.1%) are added to iron (Fe) and act as exercise set agents preventing dislocation of the iron atoms. From the image on the left it is realizable to see how the atoms of carbon (A) place in between the atoms of iron (B), preventing the sliding of the layers of iron atoms. However, in case the amount of carbon was excessive, this would have the opposite effect, causing the iron to be brickly and break easily. Some alloys are do by melting and mixing both or more metallic elements. The first alloy ever discovered was bronze, it was make of copper and tin, and was discovered during the prehistoric boundary known as the bronze age. It was to begin with used to make tools and weapons, but subsequent it has been used for ornaments, bells, statues, and bearings.Video of crash testsInvestigating the effectiveness on crumple zones during a head-on collisionSUVMass of the ropeway/kg withdrawnness from the wall /mTime taken/sDistance travelled after collision/mDetailed history of the airbag productionInvented at the start of the 1950s, it only came to wide use during the 1960s. Air bag-equipped cars have demonstrated, both in controlled tests and everyday use, their effectiveness and reliability (in frontal collisions, deaths for drivers, were lowered by 28 portion in vehicles featuring air bags).In order to answer to the increased of safety concerns of the consumers, the federal official government has forced all car manufacturers to upgrade the safety features installed on their cars. The incision of Transportation (DOT) regulations require that all cars change in the US, being produced starting from year 1990, had to feature a still simplicity system. Passive bar systems are shelter systems that require no activation by the driver and usually are set to be automatic seat belts and air bags. For air bags, until year 1994 the regulations only require a drivers air bag and must include passive protection on the passengers side (seatbelts). Later, in 1991, a new law required both driver and passenger air bags in all cars by year 1998 and in light trucks and vans by year 1999.Air bags are inflatable cushions designed to protect car passengers from serious or even fatal injury in case of a collision. The air bag is part of a system, also known as an air cushion restraint system (ACRS) or an air bag supplemental restraint system (SRS) (they are called supplemental because the air bag is designed to supplement the protection of seat belts). When detecting a collision, the air bags inflate instantly to provide the passenger with a big gas-filled cushion.A typical air bag system consists of an air bag module (containing an inflator or gas generator and an air bag), crash sensors, a diagnostic monitoring unit, a steering wheel connecting coil, and an indicator lamp. These components are all interconnected by a wiring harness and powered by the vehicles battery.Air bag sensors are specifically designed to prevent the air bag from inflating when the car travels over a bump or in case of a minor collision.In a frontal impact alike to hitting a solid obstacle at a speed of 14.5 Km/h, the sensors located in the front of the car detect the sudden deceleration and publicise an electrical signal activating an inciter. The initiator is similar to a light lightbulb and contains a thin wire that heats up, breaking through the propellant chamber. This sudden sagacity causes the solid chemical propellant, usually sodium azide, sealed up inside the inflator to undergo a very quick chemical reaction. This controlled reaction produces harmless blasts of the nitrogen gas that inflates the air bag.The resulting nitrogen gas fills the nylon bag in less than one-twenty-fifth (1/25) of a second, opening its plastic cover on the stirring wheel and inflating in front of the passenger before this hits the stirring wheel. As the occupant hits the inflated bag, the nitrogen gas is pushed out through some openings at the back of the bag. The bag remains fully inflated for no longer than tenth (1/10) of a second and is almost only deflated by troika-tenths (3/10) of a second after the impact with the passenger. Talcum gunpowder or edible corn starch is used to line the inside of the air bag and is released from the air bag as it is undecided causing the characteristic white cloud.Components of an airbagAn air bag is formed by three main pa rts the nylon bag, the inflator, and the propellant. The bag is made from a woven nylon material and can differ in shape and size depending on the specific vehicle safety requirements. Talcum powder or corn starch is used when handling the air bag, since either of the two substances prevents the woven nylon fabric from sticking together and makes assembling process easier.The inflator body is made from either stamped stainless steel or cast aluminium. Inside the inflator body there is a tense assembly formed by a stainless steel wire mesh with ceramic material held in between. When the inflator body is assembled in the factory, the filter assembly is wrapped by a metal foil to represent the filter sealed preventing propellant contamination.The propellant, typically sodium azide ,in the form of black pellets, is unite with an oxidizer and is usually located inside the inflator body between the filter assembly and the initiator.EvaluationWhile analysing how I dealt with the conve ntion Four cast off, I spy some facts that I could have improved, hence improvements that could be done in how my Group Four has worked. The members of my Group Four Project were Jacopo Mauro, Daniel Gardin, Maria Airchinsky, Edoardo Nalon and Laure Rasscheart. I noticed that when we started to work at the ejection, we werent working as a team, as we still didnt know what we really had to do, as time passed we got to know each other wear out and gained more confidence, thus, we started to work more as a team and we managed to assign tasks inside within the group, for example Edoardo had to contact some car stores and to gather information about the crumple zones and the materials used in the car production, Jacopo and Daniel were the ones who worked on the physics experiment, since they are the two members of the group who have taken the physics course, while Laure, Maria and I did the chemistry experiment, since we had the idea of the inflation of a balloon as a representation of an airbag.The project could have been done in a more efficient way we upset a lot of time to rattling start with various ideas, set the experiments, and start working as a group, although it is possible to recognize the fact that our problems in getting organized were also due the fact that the members of the group never had study periods at the same time. Probably, something that could have really helped our report was to have a leader perhaps not the smartest, but the one who could have made sure that everyone who was actually talk with their tasks, and not wait for the last bite to do so. Perhaps he/she could have given the others some deadlines, and set up meetings to see how everyone was doing.Another thing that we could have improved in our Group 4 Project was that we didnt have many meetings, we had also the summer to work on it, and we didnt really do much, so we waited for September when we came back from vacations to start again to worry about finishing the projec t.Moreover, every member of the group was at a different level in chemistry and math, for example Jacopo and Daniel are very good at chemistry and physics, in fact they chose the scientific course, while Laure, Edoardo, Maria and I dont even take physics and arent objectively very good in chemistry.However, what emerged from our difficulties was a interlocking and elaborated project, a research on an important thematic such as safety in the streets, focusing on car accidents. Our project could be expand on an international scale by suggesting other schools to perform the same research as we did, hence rising internationally the awareness in students on how chemistry and physics are important on a daily basis, how these subjects are at the base of our most important well-informed issues.