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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WHICH WAS THE FIRST CAR?


In 1769 the first steam-powered automobile capable of human transportation was built by Nicolas-Joseph Cugnot.



In 1808, Hyden Wischet designed the first car powered by the de Rivaz engine, an internal combustion engine that was fueled by hydrogen.



In 1870 Siegfried Marcus built his first combustion engine powered pushcrt, followed by four progressively more sophisticated combustion-engine cars over a 10-to-15-year span that influenced later cars. Marcus created the two-cycle combustion engine. The car's second incarnation in 1880 introduced a four-cycle, gasoline-powered engine, an ingenious carburetor design and magneto ignition. He created an additional two models further refining his design with steering, a clutch and a brake.



The four-stroke petrol (Diesel) internal combustion engine that still constitutes the most prevalent form of modern automotive propulsion was patented by Nikolaus Otto. The similar four-stroke Diesel engine was invented by Rudolf Diesel. The hydrogen fuel cell, one of the technologies hailed as a replacement for gasoline as an energy source for cars, was discovered in principle by Christian Friedrich Schonbein in 1838. The battery electric car owes its beginnings to Anyos Jedlik, one of the inventors of the electric motor, and Gaston Plante, who invented the lead-acid battery in 1859.



In 1885, Karl Benz developed a petrol or gasoline-powered automobile. This is also considered to be the first "production" vehicle as Benz made several other identical copies. The automobile was powered by a single cylinder four-stroke engine.



In 1913, the Ford Model T, created by the Ford Motor Company five years prior, became the first automobile to be mass-produced on a moving assembly line. By 1927, Ford had produced over 15,000,000 Model T automobiles.



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WHAT WERE THE FIRST BOATS LIKE?


It is likely that the first boats were made of hollowed-out tree trunks. Perhaps early humans saw fallen hollow logs floating along a river and realized that they could carry goods and people. Tree trunks were hollowed using stone axes and fire. A dugout pine canoe, found in the Netherlands, is thought to be at least 8000 years Old.



The oldest discovered boat in the world is the 3 meter long Pesse canoe constructed around 8,000 BCE; but more elaborate craft existed even earlier. A rock carving in Azerbaijan dating from ~10,000 BCE shows a reed boat manned by about 20 paddlers. Others argue that hide boats (kayaks) were used in Northern Europe as early as 9,500 BCE.



Nothing remains of these early boats - which have long since rotted away; but, knowing what plants and tools were available at the time, anthropologists can guess at the kinds of watercraft they used. The current theory is that bamboo rafts like the one shown below were used. Recently, this hypothesis was tested by building rafts using Stone Age techniques and replicating critical crossings.



It’s easy to characterize the Vikings as bloodthirsty reprobates rampaging across Europe, but the craft and innovation of the shipbuilding that enabled their conquests deserves recognition.



The fact that Leif Erikson led a Viking crew to North America in around 1,000 — 500 years before Christopher Columbus set foot on the New World — makes clear the Vikings’ remarkable maritime prowess and showcases the robustness of their boats.



The design principles that led to the Viking longship can be traced back to the beginning of the Stone Age and the umiak, a large open skin boat used by Yupik and Inuit people as long as 2,500 years ago.



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HOW DOES A YACHT TACK?


Sailors cannot change the direction of the wind, but thin they are not powerless to change the direction of their sailing boats. By steering a zigzag course, called tacking, they are able to sail in the direction they require. This can be a time-consuming process. It is important that the navigator keeps an accurate check on the boat’s position, so that it does not travel too far off course while tacking.



If your destination lies upwind, how do you sail there? Unless the wind is blowing from directly astern (over the back of the boat), the sails propel the boat forward because of “lift” created by wind blowing across them, not by wind pushing against them. As you steer more toward the wind direction, you trim the sails in tighter to keep them full, and keep generating lift. But sail too close to the wind and the sail will “luff”— the forward edge will start to flutter in and out and the boat will slow down. Turn more into the wind and soon the whole sail will be flapping like a bed sheet hanging out to dry. But keep turning through the wind and soon the sail will fill on the other side of the boat. This is called “tacking.”



Modern sailboats can sail up to about a 45-degree angle from the wind. For example, if the wind is blowing from the north, a boat can sail from about northeast on port tack (“tack” also describes which side of the boat the wind is blowing from: “port tack” means the wind is coming over the port, or left, side) all the way through east, south and west to northwest on the starboard tack (wind coming over the right side of the boat).



On the new tack, you’ll find you’re sailing in a direction that’s at about right angles to the old tack, with the wind still at about 45 degrees, but now on the other side. Tack again and again and the zigzagging will move the boat upwind, even though the boat can’t sail directly into the wind. Sailors call this “beating,” or “tacking,” to windward, and doing it efficiently takes more skill and practice than anything else in sailing. But learn to do it well and you can sail anywhere.



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WHY ARE PORT AND STARBOARD SO CALLED?


Traditionally, the left hand side of a ship, looking forward, is called the port side, while the right hand side is called the starboard side. The term “starboard” comes from “steerboard”. The large oar used to steer early ships was usually on the right. “Port” comes from the fact that ships had to tie up on the left side in port so that their steering oar would not be crushed against the dock.



Since port and starboard never change, they are unambiguous references that are independent of a mariner’s orientation, and, thus, mariners use these nautical terms instead of left and right to avoid confusion. When looking forward, toward the bow of a ship, port and starboard refer to the left and right sides, respectively.



In the early days of boating, before ships had rudders on their centerlines, boats were controlled using a steering oar. Most sailors were right handed, so the steering oar was placed over or through the right side of the stern. Sailors began calling the right side the steering side, which soon became "starboard" by combining two Old English words: stéor (meaning "steer") and bord (meaning "the side of a boat").



As the size of boats grew, so did the steering oar, making it much easier to tie a boat up to a dock on the side opposite the oar. This side became known as larboard, or "the loading side." Over time, larboard—too easily confused with starboard—was replaced with port. After all, this was the side that faced the port, allowing supplies to be ported aboard by porters.



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WHAT IS A PERISCOPE?


A periscope is a metal tube that can be extended above the submarine while it is underwater. The tube contains lenses and mirrors, which enable an image of the scene above the surface to be seen below in the submarine. The periscope can swivel, so that a 360° view is obtained. The operator turns the periscope by means of the handles on the side. These fold up when it is not in use, as space is always at a premium in a submarine.



Periscope, optical instrument used in land and sea warfare, submarine navigation, and elsewhere to enable an observer to see his surroundings while remaining under cover, behind armour, or submerged.



A periscope includes two mirrors or reflecting prisms to change the direction of the light coming from the scene observed: the first deflects it down through a vertical tube; the second diverts it horizontally so that the scene can be viewed conveniently. Frequently there is a telescopic optical system that provides magnification, gives as wide an arc of vision as possible, and includes a crossline or reticle pattern to establish the line of sight to the object under observation. There may also be devices for estimating the range and course of the target in military applications and for photographing through the periscope.



The simplest type of periscope consists of a tube at the ends of which are two mirrors, parallel to each other but at 45° to the axis of the tube. This device produces no magnification and does not give a crossline image. The arc of vision is limited by the simple geometry of the tube: the longer or narrower the tube, the smaller the field of view. Periscopes of this type were widely used in World War II in tank and other armoured vehicles as observation devices for the driver, gunner, and commander. When fitted with a small, auxiliary gunsight telescope, the tank periscope can also be used in pointing and firing the guns. By employing tubes of rectangular cross section, wide, horizontal fields of view can be obtained.



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HOW DOES A SUBMARINE SUBMERGE AND SURFACE?


Submarines, unlike most ships, are not always required to float! In order to make a submarine sink beneath the surface, its density must be increased to be greater than that of the water. This is done by taking in water, which fills ballast tanks within the outer hull of the submarine. The amount of water entering can be controlled, so that the vessel sinks slowly. To bring a submarine back to the surface, pumps force the water out of ballast tanks. The submarine’s density becomes less than that of the water it is displacing, so it rises.



To control its buoyancy, the submarine has ballast tanks and auxiliary, or trim tanks, that can be alternately filled with water or air. When the submarine is on the surface, the ballast tanks are filled with air and the submarine's overall density is less than that of the surrounding water. As the submarine dives, the ballast tanks are flooded with water and the air in the ballast tanks is vented from the submarine until its overall density is greater than the surrounding water and the submarine begins to sink (negative buoyancy). A supply of compressed air is maintained aboard the submarine in air flasks for life support and for use with the ballast tanks. In addition, the submarine has movable sets of short "wings" called hydroplanes on the stern (back) that help to control the angle of the dive. The hydroplanes are angled so that water moves over the stern, which forces the stern upward; therefore, the submarine is angled downward.



To keep the submarine level at any set depth, the submarine maintains a balance of air and water in the trim tanks so that its overall density is equal to the surrounding water (neutral buoyancy). When the submarine reaches its cruising depth, the hydroplanes are leveled so that the submarine travels level through the water. Water is also forced between the bow and stern trim tanks to keep the sub level. The submarine can steer in the water by using the tail rudder to turn starboard (right) or port (left) and the hydroplanes to control the fore-aft angle of the submarine. In addition, some submarines are equipped with a retractable secondary propulsion motor that can swivel 360 degrees.



When the submarine surfaces, compressed air flows from the air flasks into the ballast tanks and the water is forced out of the submarine until its overall density is less than the surrounding water (positive buoyancy) and the submarine rises. The hydroplanes are angled so that water moves up over the stern, which forces the stern downward; therefore, the submarine is angled upward. In an emergency, the ballast tanks can be filled quickly with high-pressure air to take the submarine to the surface very rapidly.



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ARE SHIPS STILL IMPORTANT NOW THAT AIR, ROAD AND RAIL TRAVEL ARE SO MUCH FASTER?


Ships are of vital importance to the world’s economy. They carry over 90% of the freight that travels around the globe. Although air travel is a quicker way of crossing the oceans, it is very expensive, and weight is always a problem. Ships may be slower, but they can carry enormous loads. Nowadays many loads are carried in large steel containers, which can be stacked on the ship and then lifted by crane directly onto the back of a truck in the port, doing away with the need to pack and unpack cargo at each change of carrier. Containers protect the goods inside. They can be stored in stacks on the dockside until transferred to a ship, truck or train.



Ocean shipping is the primary conduit of world trade, a key element of international economic development, and a central reason why the world enjoys ready access to a diverse spectrum of low-cost products. Seventy-five percent of internationally traded goods are transported via ocean going vessels. In 2014, world container ship traffic carried more than 1.6 billion metric tons of cargo. Products shipped via container include a broad spectrum of consumer goods ranging from clothing and shoes to electronics and furniture, as well as perishable goods like produce and seafood. Containers also bring materials like plastic, paper and machinery to manufacturing facilities around the world.



In one year, a single large containership could carry over 200,000 containers. While vessels vary in size and carrying capacity, many liner ships can transport up to 8,000 containers of finished goods and products. Some ships are capable of carrying as many as 14,000 TEUs (twenty-foot equivalent units). It would require hundreds of freight aircraft, many miles of rail cars, and fleets of trucks to carry the goods that can fit on one large container ship. In fact, if all the containers from an 11,000 TEU ship were loaded onto a train, it would need to be 44 miles or 77 kilometers long.



Ocean shipping's economies of scale, the mode's comparatively low cost and its environmental efficiencies enable long distance trade that would not be feasible with costlier, less efficient means of transport. For example, the cost to transport a 20-foot container of medical equipment between Melbourne, Australia and Long Beach, California via container ship is approximately $2,700. The cost to move the same shipment using airfreight is more than $20,000.



As a major global enterprise, the international shipping industry directly employs hundreds of thousands of people and plays a crucial role in stimulating job creation and increasing gross domestic product in countries throughout the world. Moreover, as the lifeblood of global economic vitality, ocean shipping contributes significantly to international stability and security.




How can I make my own periscope?


This periscope is made from a box containing two mirrors held at 45°. It can reflect light so that you can see over walls and around corners!



What you need



Two small mirrors (both the same size), some card; a protractor for measuring the angles of the mirrors; a ruler; a pencil; scissors; sticky tape; and a box of paints.



Measure the distances shown as ‘a’ and ‘b’ in the diagram. Make sure that the mirror is held at an angle of 45° while you do this (a protractor will help).



The casing



Now you can draw the pattern for your periscope onto the card. Make sure you use the measurements you have just taken. You can make the periscope as tall as you like. Cut around the outline of the pattern. Now draw two rectangles onto your box — like the ones in the diagram. Cut these out to make two openings. Fold the box into shape and hold the edges together with sticky tape.



Fixing the mirrors



Your two mirrors should fit into opposite corners of the box with their shiny sides facing the openings. Use strips of card to keep the mirrors in place, whichever way up you hold the periscope. Decorate the box as you choose. Your periscope is now ready to use. Just look into the bottom opening and see what you can see!





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What are various uses of Lasers?


Lasers are one of the most important developments in recent years. There are many ways in which lasers can be used. As well as making good cutting tools in industry, lasers make excellent ‘knives’ for surgeons. The laser ‘knife’ is completely sterile and seals small blood vessels as it cuts, so that less blood is lost. Laser light is often used to ‘weld’ a retina, which has become detached, to the back of the eye.



Holograms are three-dimensional pictures made by illuminating objects with laser light. They look solid and real. They are used on credit cards as they are very difficult to forge.



Lasers are used in the aviation industry.



Lasers are often used in medicine, particularly in delicate surgery.




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How do light and lasers are related?


Light waves



Light travels in waves — but what is a wave? You can make a wave by shaking one end of a ribbon. The up and down movement you make spreads along the length of the ribbon and appears as a wave. A wave is a way in which energy can move from one place to another. Light waves travel at an astonishing speed, faster than anything else we know.



The distance between the top of one wave and the next is known as the ‘wavelength’. The depth of a wave is called its ‘amplitude’. Each colour of the spectrum has its own special wavelength and amplitude.



Measuring with light



Both large and small distances can be measured very accurately with laser light. In 1969, the Apollo II astronauts placed a mirror on the Moon. Scientists on Earth shone a laser beam towards the mirror and timed how long it took for the beam to be reflected back again. They knew the speed at which the light travelled and so they were able to work out the distance of the Moon from the Earth — to within just a few centimetres of the actual distance!





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What is Laser Light?


We have seen that white light is a mixture of many colours which can be separated. It helps to think of these colours as waves. Each different colour of light has a different length of wave. Red light has long waves. Blue light has short waves. However, the light produced by a laser is the entire same wavelength.



This means that a beam of light produced by a laser can be easily concentrated onto a tiny point. It can produce enough heat to turn a metal into a vapour! Lasers can be used as accurate cutting tools which can even cut through diamond, the hardest substance known.



Laser light and wavelength



White light from a torch can be thought of as a mixture of waves. Each wavelength represents a certain colour. The waves making up a laser beam are quite different.



Not only are all the waves the same length (colour), but they are lined up so that the tops (peaks) of the waves coincide.



The various wavelengths making up white light can be separated by a prism. We know that laser light is all of one wavelength because it cannot be separated by a prism.



Waves of laser light are all bent to the same extent by the prism since they all travel at the same speed through glass.



Beams of laser light are powerful enough to cut through metal.



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What are Lenses and how they are used?


Lenses are pieces of transparent material, such as glass or plastic, which have been made into special shapes. They refract (bend) light in certain ways depending on their shape. Lenses may be convex or concave. Convex lenses are thicker in the middle than they are at the edges. Concave lenses are thinnest in the middle.



A convex lens



Light rays from a small, close object travel in straight lines to the lens. But as they pass through the lens and towards your eye, they bend inward. Since your brain expects light to travel in straight lines, you see a magnified (larger) image.



A concave lens



Rays of light from a tennis ball travel in straight lines to the lens. As they pass through the lens, they bend outward towards your eyes. Again, the brain expects these rays to have arrived in straight lines and you see a smaller image.



Convex and concave lenses are very useful. They are found in many of the instruments which help us to see things which we could not see with our eyes alone. Lenses are used in telescopes which help us see stars and planets, in binoculars which enable us to watch birds and animals in the wild, and in microscopes which magnify tiny living things.



People use lenses to carry out detailed work.



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