HOW DO PLANES FLY?


Aeroplanes fly when two of the four forces acting upon them are greater than the other two. The force of thrust, created by the aeroplanes propellers or jet engines, moves the plane forward. The force of lift is caused by air flowing over the wings. This keeps the plane in the air. The two forces working against thrust and lift are gravity, which pulls the plane towards the Earth, and drag, caused by air resistance, which slows the plane’s forward motion.



Four forces act on a plane in flight. When the plane flies horizontally at a steady speed, lift from the wings exactly balances the plane's weight and the thrust exactly balances the drag. However, during takeoff, or when the plane is attempting to climb in the sky, the thrust from the engines pushing the plane forward exceeds the drag (air resistance) pulling it back. This creates a lift force, greater than the plane's weight, which powers the plane higher into the sky.



If you've ever watched a jet plane taking off or coming in to land, the first thing you'll have noticed is the noise of the engines. Jet engines, which are long metal tubes burning a continuous rush of fuel and air, are far noisier (and far more powerful) than traditional propeller engines. You might think engines are the key to making a plane fly, but you'd be wrong. Things can fly quite happily without engines, as gliders (planes with no engines), paper planes, and indeed gliding birds readily show us.



Newton's third law of motion explains how the engines and wings work together to make a plane move through the sky. The force of the hot exhaust gas shooting backward from the jet engine pushes the plane forward. That creates a moving current of air over the wings. The wings force the air downward and that pushes the plane upward.




HOW ARE UNDERGROUND RAILWAYS BUILT UNDER EXISTING CITIES?


Beneath cities are the foundations of large buildings and many pipes carrying water, electricity, gas and telephone cables. Builders have either to tunnel very deeply or to use a technique called “cut-and-cover”, which means that they run the railway under existing roads, so that they simply have to dig a huge trench along the road, build the railway, and cover it up again.



The building method used for many years was a so-called “cut-and-cover” system. It was easier to dig out a large open hole in the road, build the arch of the false tunnel with bricks, and then refill the hole with the dug-out material. As a result, the first underground lines were not very deep, something that tends to be the case with the older underground lines in major cities.



One of the companies of the time, C&SLR, was the first to use electric traction for pulling the trains, as well as a new method for digging circular tunnels, using a technology known as “shield tunneler”, which initially was opearated manually. The front part was used to dig out a circular section and the tunneling machine was called the Greathead Shield. Later on, the shield became mechanical and the machine advanced much more rapidly and could cut through any type of material. Today, these are called TBMs, or Tunnel Boring Machines.



These tunnelling machines made it possible to dig under the city at a greater depth and create new underground lines on another level: they could dig under buildings and keep away from electricity lines, sewers and other infrastructures. They could even dig under the Thames.



Fast forward 155 years to our times. A massive new rail undertaking spanning over 100 km, more than 40 km of which run below the streets of London, connecting with the underground network at some points.






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WHERE WAS THE FIRST UNDERGROUND RAILWAY BUILT?


The world’s first city underground railway line was opened in 1863 in London. It was called the Metropolitan. The London Underground (also known simply as the Underground or by its nickname the Tube) is a public rapid transit system serving London region, England and some parts of the adjacent counties of Buckinghamshire, Essex and Hertfordshire in the United Kingdom.



The Underground has its origins in the Metropolitan Railway, the world's first underground passenger railway. Opened in January 1863, it is now part of the Circle, Hammersmith & City and Metropolitan lines; the first line to operate underground electric traction trains, the City & South London Railway in 1890, is now part of the Northern line. The network has expanded to 11 lines, and in 2017/18 carried 1.357 billion passengers, making it the world's 12th busiest metro system. The 11 lines collectively handle up to 5 million passengers a day.



The system's first tunnels were built just below the ground, using the cut-and-cover method; later, smaller, roughly circular tunnels—which gave rise to its nickname, the Tube—were dug through at a deeper level. The system has 270 stations and 250 miles (400 km) of track. Despite its name, only 45% of the system is underground in tunnels, with much of the network in the outer environs of London being on the surface. In addition, the Underground does not cover most southern parts of London region, and there are only 29 stations south of the River Thames.





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WHAT IS A COWCATCHER?


A cowcatcher is a V-shaped metal part on the front of a train, designed to push obstacles — including cows! — Off the line before the wheels hit them. The American Denver and Rio Grande steam engine has an example.



Cowcatchers were wooden bars added to a metal frame and fitted to electric corporation trams in cities across Britain as they were set up in the very early 1900. A cow catcher is a device attached to the front of a train or tram in order to clear obstacles off the track.



Invented in 1838 by British engineer Charles Babbage, this device is now used mostly in North America, as modern European railway systems tend to be fenced off and less susceptible to the danger of foreign objects on the track. In the locomotive industry, a cow catcher is more commonly referred to as a pilot. A cow catcher is typically a shallow, V-shaped wedge, designed to deflect objects from the track at a fairly high speed without disrupting the smooth movement of the train.



The shape serves to lift any object on the track and push it to the side, out of the way of the locomotive behind it. The first cow catcher models were constructed of a series of metal bars on a frame, but sheet metal and cast steel models became more popular, as they work more smoothly. When steam-powered locomotives became more common, the cow catcher was often supplemented with a drop coupler.



The front coupler, a device used to attach railroad cars to each other, was fashioned to hinge up and out of the way in order to prevent its catching on obstacles. Another bygone pilot model is the footboard pilot, which featured steps on which railway workers could stand and catch a ride.



In the 1960s, these pilots were outlawed and replaced with safer platforms on the front and rear of the locomotive. Today, people in the railroad industry frown upon the term "cow catcher," but the pilot is still in use. Today's pilots are much smaller and shallower than their predecessors.



Since diesel locomotives feature front cabs carrying crew, the pilot must be constructed to prevent the cab from being struck by objects deflected from the road. A separate feature known as an anticlimber is typically installed above the pilot to protect the cab.




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HOW DO TRAINS CHANGE TRACKS?


The intersections that allow a train to move over onto another track are called switches or points. Short pieces of rail are able to move across to bridge the gap between the two tracks, so that the train’s wheels cross over as smoothly as possible.



To make a train change its track, a special mechanical arrangement is made. This arrangement is known as a railroad switch and it consist of pair of rails, known as switching rails or points that are linked to one another. As the name suggests, the switching rails can direct or guide the train, either on straight path or on the diverging path which is established by a curved rail line.



The railroad switch can only be in one of the two positions at a time. If it is locked the train will change the track. If it is open, it will go straight-through. Here is animated rail-road switch demonstrating the principle and operation.



It is very important that the switch is set up carefully. Most train derailments take place at the point when it goes from one track to another track. A loose set up is a guarantee of making train jump off the track, a disaster. However, a railway authority, not only in India, but around the world has expertise the art of train track changing. Most times the process is so smooth, that one even doesn't notice it. However an experienced traveler can make out with the sound of the train, that indeed the track is changed.



Sometimes tracks are changed at the last moment to change the platform at which the train arrives. An Indian railway is overly notorious in this regard. So many times people are caught napping when they would be waiting for train at one station only to hear a last time announcement that the train is arriving at the other platform. This is especially problematic if the halt of train is of couple of minutes only, on a specific station.



In India there are mostly two railway tracks that you'll see running parallel to each other. One is known as the 'up' track, and other is 'down' track. But as soon as any railway station comes, there are plenty of tracks that one can see. This is where the train wills starts climbing from one track to another to get to the platform from where it is scheduled to leave.



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WHO INVENTED THE LOCOMOTIVE?


A Locomotive is an engine that can travel under its own power, not pulled by horses, for example. But we usually think of it as running on tracks, or tramways, as they were first called. In 1804, Richard Trevithick (1771-1833), an English inventor, designed a train to pull coal wagons in a Welsh colliery. Trevithick was convinced that steam engines had a great future and later travelled to Peru and Costa Rica, where he introduced steam engines into the silver mines.



In 1802, Richard Trevithick patented a "high pressure engine" and created the first steam-powered locomotive engine on rails.  Trevithick wrote on February 21, 1804, after the trial of his High Pressure Tram-Engine, that he "carry'd ten tons of Iron, five wagons, and 70 Men...above 9 miles...in 4 hours and 5 Mints."  Though a ponderous-sounding journey, it was the first step toward an invention that would utterly change man's relationship to time and space. 



George Stephenson and his son, Robert, built the first practical steam locomotive.  Stephenson built his "travelling engine" in 1814, which was used to haul coal at the Killingworth mine.  In 1829, the Stephenson built the famous locomotive Rocketwhich used a multi-tube boiler, a practice that continued in successive generations of steam engines.  The Rocket won the competition at the Rain-hill Trials held to settle the question of whether it was best to move wagons along rails by fixed steam engines using a pulley system or by using locomotive steam engines. The Rocket won the £500 prize with its average speed of 13 miles per hour (without pulling a load, the Rocket attained speeds up to 29 miles per hour), beating out Braithwaite and Erickson's Novelty and Timothy Hackworth's Sans Pareil.  The Stephenson incorporated elements into their engines that were used in succeeding generations of steam engines.



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WHAT IS THE GAUGE OF A RAILWAY?


The gauge of a railway is the distance between its rails. At one time, the standard gauge in several countries was 1.48m (4ft 10.25 in), which was thought to have been the width of Roman chariot tracks. Today, many different gauges are used.



In rail transport, track gauge or track gage is the spacing of the rails on a railway track and is measured between the inner faces of the load-bearing rails.



All vehicles on a rail network must have running gear that is compatible with the track gauge, and in the earliest days of railways the selection of a proposed railway's gauge was a key issue. As the dominant parameter determining interoperability, it is still frequently used as a descriptor of a route or network.



In some places there is a distinction between the nominal gauge and the actual gauge, due to divergence of track components from the nominal. Railway engineers use a device, like a caliper, to measure the actual gauge, and this device is also referred to as a track gauge.



The terms structure gauge and loading gauge, both widely used, have little connection with track gauge. Both refer to two-dimensional cross-section profiles, surrounding the track and vehicles running on it. The structure gauge specifies the outline into which new or altered structures (bridges, lineside equipment etc.) must not encroach. The loading gauge is the corresponding envelope within which rail vehicles and their loads must be contained. If an exceptional load or a new type of vehicle is being assessed to run, it is required to conform to the route's loading gauge. Conformance ensures that traffic will not collide with lineside structures.




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WHAT DO THE NUMBERS BEFORE STEAM TRAIN NAMES MEAN?


Steam locomotives are described by the arrangement of their leading, driving and trailing wheels. In fact, only the driving wheels are connected to the cylinders that provide the engine’s power. So a 2-8-2 has two leading wheels, eight driving wheels and two trailing wheels.



Under the Whyte notation for the classification of Steam locomotives, 2-8-2 represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, eight powered and coupled driving wheels on four axles and two trailing wheels on one axle, usually in a trailing truck. This configuration of steam locomotive is most often referred to as a Mikado, frequently shortened to Mike.



At times it was also referred to on some railroads in the United States of America as the McAdoo Mikado and, during the Second World War, the MacArthur.



The notation 2-8-2T indicates a tank locomotive of this wheel arrangement, the "T" suffix indicating a locomotive on which the water is carried in side-tanks mounted on the engine rather than in an attached tender.



The 2-8-2 wheel arrangement allowed the locomotive's firebox to be placed behind instead of above the driving wheels, thereby allowing a larger firebox that could be both wide and deep. This supported a greater rate of combustion and thus a greater capacity for steam generation, allowing for more power at higher speeds. Allied with the larger driving wheel diameter which was possible when they did not impinge on the firebox, it meant that the 2-8-2 was capable of higher speeds than a 2-8-0 with a heavy train. These locomotives did not suffer from the imbalance of reciprocating parts as much as did the 2-6-2 or the 2-10-2, because the center of gravity was between the second and third drivers instead of above the centre driver.



The first 2-8-2 locomotive was built in 1884. It was originally named Calumet by Angus Sinclair, in reference to the 2-8-2 engines built for the Chicago & Calumet Terminal Railway (C&CT). However, this name did not take hold.



The wheel arrangement name "Mikado" originated from a group of Japanese type 9700 2-8-2 locomotives that were built by Baldwin Works for the 3 ft 6 in (1,067 mm) gauge Nippon Railway of Japan in 1897. In the 19th century, the Emperor of Japan was often referred to as “the Mikado” in English. Also, the Gilbert and Sullivan opera The Mikado had premiered in 1885 and achieved great popularity in both Britain and America.



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WHICH WAS THE WORLD’S FIRST PUBLIC RAILWAY?


The first public railway in the world to run a regular service was opened on 27 September 1825. It ran between Stockton and Darlington in the north of England. A steam train called The Locomotion pulled 34 wagons, some of which carried coal, while others were adapted to carry passengers. Both the locomotive and its track were built to the design of George Stephenson (1781-1848). Stephenson’s background was in mining engineering. Coal mines had long used tracks to move wagons of coal, and it was with steam engines for these wagons that Stephenson first experimented.



“The world’s first public railway to use steam locomotives, its first line connected collieries near Shildon with Stockton and Darlington… The movement of coal to ships rapidly became a lucrative business, and the line was soon extended to a new port and town at Middlesbrough. While coal waggons were hauled by steam locomotives from the start, passengers were carried in coaches drawn by horses until carriages hauled by steam locomotives were introduced in 1833". 



One of the significant results of the success of the Stockton and Darlington project was the extent to which it gave support to plans for building a railway between Liverpool and Manchester.



 




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HOW WILL MOTOR CARS CHANGE IN THE FUTURE?


Two areas of car design have been researched very thoroughly in the past few years. One of these concerns fuel consumption and exhaust gases, as the realization grows that the world’s fossil fuels are polluting the atmosphere. The other is safety. It is likely that future cars will be able to prevent some accidents by assessing - the distance to an obstacle and taking evasive action without prompting from the driver.



After decades of auto technology that had evolved only marginally since the mid-20th century, experts say we’re now seeing a super-fast shift that's comparable to the industry's early days. “In the last 30 to 40 years the way cars were manufactured didn’t change much,” says Ozgur Tohumcu, CEO of the car-tech company Tantalum. “But now things are fundamentally changing — and very quickly.”  Quickly, indeed. Here's a look at some of the cool innovations we're likely to see in the next generation of cars.



Voice commands for your car



High on the list of innovations is the introduction of Alexa-like personal assistants. “You’ll be able to interact with your car through voice command,” says Tohumcu. One scenario: You might be driving and looking for a parking space. All you’ll have to do is say “Find parking,” and your vehicle will navigate you to the closest, least expensive, safest garage, based on your programmed preferences, and then pay the fee with your credit card.



Mechanic on wheels



Cars will be able to diagnose their own mechanical problems. “If it’s a software fix that’s needed, you’ll get an upgrade,” Tohumcu says. If you need to take the car to a mechanic, the car will research the options and book itself an appointment. (It will be able to renew its own insurance and look for better deals, too.)



More map options



As navigational maps get overlaid with more data, you’ll be able to choose your route based on a broadening array of criteria, including “least polluted.” “People will be taken from point A to point B through better air-quality routes,” Tohumcu says. “If you’re an older person or you have chronic asthma, this becomes a real benefit.” Other possibilities: “safest route” and “most scenic.”



Custom-designed vehicles



Using 3D printing technology, Arizona-based Local Motors is 3D-printing cars. “They work with pre-determined engine types and 3D print cars on top of those engines,” Tohumcu says. “You can pick and choose features from different cars to create your own.” That means we may see all kinds of interesting-looking cars on the street, he says. “These cars won’t be cheap, but if you really want to stand out it’s one way to go.”



Shared autonomous vehicles



Self-driving cars are already here and doing well in safety tests, says Alan Brown, executive vice president at NuVinAir, an automotive-industry startup, who previously spent 27 years with Volkswagen. The twist he predicts: People will be able to share these cars. “Cars today sit unused 80 percent of the time,” he says. “If the car is self-driving, we have a wonderful opportunity for people to co-own it and pay only for the portion of the car they use.” He sees the potential, in particular, for younger people who may not be able to afford their own vehicle, people with disabilities who aren’t able to drive, and older people who may need to stop driving.



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HOW DO RACING CAR DRIVERS ACHIEVE HIGH SPEEDS?


Formula 1 driver cannot win races by themselves. Large teams of mechanics and technicians are needed to enable the car to perform well. The driver spends more time testing the car than he does racing, and no aspect of the vehicle is ignored. Even while the car is waiting at the start of a race, special electric heaters are warming the tyres so that they give their best performance. Every second counts in motor racing, so mechanics practice until they can change all four tyres of the car in under three seconds! Controlling the car at high speed puts enormous physical and mental strain on the driver. There is no power steering in Formula 1 cars, so the driver needs great strength and split-second reactions.



Drag racing sounds easy, but it is one of the most difficult types of game racing. If you want to achieve the race, you must prepare and check all the things, such as a good racing equipment, the racing system, and the driver status. For this, the most important thing that you should prepare a good battery for your racing car.



A good racing device is the indispensable for racing, you should prepare a good racing car and long driving battery to keep the car long run. As we know that long driving battery should have high capacity, but this will also add its weight. More weight will lower the racing speed that may lose the race.



Choosing a racing oil to reduce the friction for maximum power and cooler engine temperatures, resulting in improved lap times and longer-lasting equipment.



Practice to increase your reaction time in a drag race whenever you get the chance, every driver and every car is different, and they are affected by variables such as turbo lag, tire type and the type of fuel used.



Many people know that if you want to keep racing car driving long and maintain fast racing speed, you should increase the battery voltage. Tattu battery adopts leading-edge battery technology that can provide an optimal solution for racing car. It will be the best choice for your race car.



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WHAT IS THE DIFFERENCE BETWEEN A VETERAN CAR AND A VINTAGE CAR?


A veteran car was made between 1896 and 1903, while a vintage car was built after 1904 and before 1930.



At what indeterminable point in time does an old car become a Classic? It may be easier to find the true location of Camelot than be able to find agreement between various groups of automotive enthusiasts as to what constitutes a Classic Car. It is very easy to define a Veteran Car, as they were, quite simply, built before the First World War. Similarly a Vintage Car was built before 1930, and Post Vintage referred to cars from the 30s until the end of WWII, however after this point it all becomes a bit hazy.



Some automotive organisations may refer to a car made in the 1940s as a Classic, while others my consider cars from the 1980s to Classics. Classic Car insurance generally kicks in for cars 20 years and older. However, there is also the UK Road Tax exemption on Classic Cars. When this was first introduced, a car needs to be more than 25 years old to be eligible. However now, due to a change in the rules, this only applies to cars built before 1973. So does that make everything built pre-1973 officially classic and everything built after not and never to be deemed so?



Few people would deny that the Ferrari Testarossa was a “Classic” from the moment she was launched in 1984, however hardly anyone would deem a VW Passat from the early 70s as a Classic. The Federation of British Historic Vehicle Clubs is campaigning for the reintroduction of the rolling scheme, but with a 30 year threshold. Yet, as shown above, defining a Classic by age alone oversimplifies it somewhat.



For a car to be considered and appreciated as a Classic there needs to be an aesthetic appeal. This could be for its design credentials or an element of timeless engineering beauty, combined with the ability to turn heads. When pulling up at a country hotel, do other guests stop to stare or ask questions? A Classic Car, like a classic beauty, needs to have that oh-so-subtle envy factor.



Being pragmatic, there is a value equation with Classic Cars which is associated with rarity, desirability and of course age. If the car has stopped going down in value and begun to rise again then that indicates that it has reached Classic status. A concourse car is more desirable than a restored version.




WHAT IS A CUSTOM CAR?


A custom car is one that has been altered from the manufacturer’s original specifications to suit the wishes of its owner. This may involve painting it with extraordinary designs, making the engine more powerful, or even “stretching” it by cutting the entire car in half and inserting additional body parts. Some cars have been made very long indeed by this method.



The one Custom car has 26 wheels and contains a swimming pool! There’s a helicopter parked on the car’s boot area. However, it’s not a fake and rather is the world’s longest car ever built. Called the “American Dream,” this massive limousine was built by California custom car guru Jay Ohrberg. It measures in at a stunning 100 feet long, which earned it the title of being the longest car, certified by Guinness World Records in the mid-’90s. Ohrberg chose a golden 1970s Cadillac Eldorado as the starting point for his mega project, which he began working on in the late 1980s. The 100-foot long stretched limo has a whopping 26 wheels and two separate driver’s cabins.



To make the American Dream even more special, Ohrberg decided to give it some of the most outrageous amenities, which include a helipad. In addition to that, the stretched limo has a Jacuzzi, diving board, king-sized water bed, as well as a small lace and candelabra-festooned living room. The American Dream was a show car which was trailered on flatbed trucks from location to location. It was leased to a company which used it as a promotional vehicle until the lease ran out. It was left abandoned in a New Jersey warehouse for many years before it resurfaced in 2012 at a salvage auction in a very bad state, which seemed like the end of the road for the American Dream. However, the New York’s Automotive Teaching Museum acquired it in 2014.





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WHAT ARE THE MAIN SYSTEMS OF A CAR?


Like the human body, a car can be thought of as having systems with different functions, all working together to make the vehicle operate effectively.



 The modern vehicle is made up of a variety of parts and components all working together to achieve a final product: “The Car”. These parts and  components are assembled in groups to perform various tasks. These groups are referred to as systems. There are many systems that make up the modern vehicle, some working with others to perform a larger, sometimes more complex, task and others working individually in order to accomplish an individual job. The following is a list of the major systems that make up the modern vehicle.




  • The Engine – including lubrication and cooling.

  • The Fuel System – including evaporative emission.

  • The Ignition System

  • The Electrical System – including starting and charging.

  • The Exhaust System –including emission control.

  • The Drive Train – including the transmission.

  • The Suspension and Steering Systems

  • The Brake System

  • The Frame and Body



There are many other systems which contribute to the modern vehicle such as the Supplementary Restraint System (seat belts and air bags), Climate Control System (designed to provide passengers with a comfortable environment in which to ride) and everybody’s favourite the Sound System.



THE ENGINE



The engine is the vehicle’s main source of power. This is where chemical energy is converted into mechanical energy. The most popular type of engine is referred to as the Internal Combustion Engine. This engine burns an air/fuel mixture inside itself in order to drive a series of pistons and connecting rods that in turn rotate a crankshaft providing us with a continuous rotating motion with which to drive the vehicle and other components. The engine also incorporates others systems, including the lubrication system and the cooling system, all working efficiently together. The cooling system maintains the engine at an ideal operating temperature while the lubrication system ensures that all the moving parts are kept well-oiled in order to provide a long serviceable life.



Electrical system



As well as moving the wheels, the engine also powers an alternator, or dynamo, which generates electrical current. This current is stored in the battery. This supplies energy for the car’s lights, windscreen wipers, radio and such features as electric windows.



Suspension system



The suspension is a system of springs and shock absorbers that prevents every jolt caused by an uneven road surface being felt by the driver and passengers inside the car.



Transmission system



The transmission system consists of the crankshaft, gears and the differential. This is a system of gears on the axles that allows the wheels to travel at different speeds when going round corners, when the outer wheel travels further than the inner one.



Braking system



Each wheel has a brake unit, connected to the brake pedal by a tube full of brake fluid. Pushing the pedal forces the fluid down the tube, causing a brake shoe to press against a metal disk or drum on the inside of the wheel. Friction causes the wheels to slow and stop.





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HOW DOES THE INTERNAL COMBUSTION ENGINE WORK?


Internal combustion engines are usually fuelled by petrol or diesel. This fuel is burnt (combusted) within metal cylinders. The burning fuel causes a piston to move up and down inside each cylinder, and it is this upward and downward movement that is translated into a turning movement by the crankshaft, causing the axles and wheels to turn and the car to move.



Combustion, also known as burning, is the basic chemical process of releasing energy from a fuel and air mixture.  In an internal combustion engine (ICE), the ignition and combustion of the fuel occurs within the engine itself. The engine then partially converts the energy from the combustion to work. The engine consists of a fixed cylinder and a moving piston. The expanding combustion gases push the piston, which in turn rotates the crankshaft. Ultimately, through a system of gears in the powertrain, this motion drives the vehicle’s wheels.



There are two kinds of internal combustion engines currently in production: the spark ignition gasoline engine and the compression ignition diesel engine. Most of these are four-stroke cycle engines, meaning four piston strokes are needed to complete a cycle. The cycle includes four distinct processes: intake, compression, combustion and power stroke, and exhaust.



Spark ignition gasoline and compression ignition diesel engines differ in how they supply and ignite the fuel.  In a spark ignition engine, the fuel is mixed with air and then inducted into the cylinder during the intake process. After the piston compresses the fuel-air mixture, the spark ignites it, causing combustion. The expansion of the combustion gases pushes the piston during the power stroke. In a diesel engine, only air is inducted into the engine and then compressed. Diesel engines then spray the fuel into the hot compressed air at a suitable, measured rate, causing it to ignite.




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