Forces and Friction
From the time of Isaac Newton, the concept of forces became understood. "Every action has an equal and opposite reaction". What does this mean? Basically, if you take any body, for example a book, floating in outer space for example, and give it a push, it will move off at a speed proportional to the force you applied. If you put the same book on Earth, for example on a table, and gave it a push, it would move a little bit and stop. This is because another force is acting upon the book as well as your push force. This force is friction. If you want to get anywhere fast, therefore, friction becomes a problem.
The ancients got over this problem on land by inventing (or discovering) the wheel - a device which physically levitates a body above the surface over which it is travelling, to virtually negate the effects of the contact friction upon it. The early days of steam travel allowed the human race increasingly faster means of transport, and, with these, more discoveries happened. The faster you go, even with the most polished and rounded of wheels, friction once again increases, this time in the form of aerodynamic drag. This is a force generated by losing movement energy (inertia) to air molecules as they are struck by a moving body, such as a train. The faster or more blunt a surface hitting these molecules creates more and more drag (or air resistance). Therefore, in order to keep speeds up, streamlining had to be applied. The trains such as The Flying Scotsman, part of Sir Nigel Gresley's Pacific Class of locomotive [Monro, 2005], were famous because they were made as "slippery" as possible to oncoming air particles, shaped as close to a the shape of a bullet as possible. Aeroplanes after the Wright Brothers' first flight also had to become increasingly streamlined, to the extent of Concorde and the SR-71 Blackbird, which could not only go fast, but also break the sound barrier many times over.
Streamlining was also applied to nautical craft, a.k.a., boats. It's no coincidence that an oil tanker can go nowhere near as fast as a Formula 1 Racing Boat. Why? The racing boat is slipstreamed against the water. However, water is about a thousand times more dense than air, and very much more viscous. The results of these two properties are that streamlining the hull of a boat against water doesn't mean that with the same power you can go as fast as you would do in air.
Forces and FrictionFrom the time of Isaac Newton, the concept of forces became understood. "Every action has an equal and opposite reaction". What does this mean? Basically, if you take any body, for example a book, floating in outer space for example, and give it a push, it will move off at a speed proportional to the force you applied. If you put the same book on Earth, for example on a table, and gave it a push, it would move a little bit and stop. This is because another force is acting upon the book as well as your push force. This force is friction. If you want to get anywhere fast, therefore, friction becomes a problem.The ancients got over this problem on land by inventing (or discovering) the wheel - a device which physically levitates a body above the surface over which it is travelling, to virtually negate the effects of the contact friction upon it. The early days of steam travel allowed the human race increasingly faster means of transport, and, with these, more discoveries happened. The faster you go, even with the most polished and rounded of wheels, friction once again increases, this time in the form of aerodynamic drag. This is a force generated by losing movement energy (inertia) to air molecules as they are struck by a moving body, such as a train. The faster or more blunt a surface hitting these molecules creates more and more drag (or air resistance). Therefore, in order to keep speeds up, streamlining had to be applied. The trains such as The Flying Scotsman, part of Sir Nigel Gresley's Pacific Class of locomotive [Monro, 2005], were famous because they were made as "slippery" as possible to oncoming air particles, shaped as close to a the shape of a bullet as possible. Aeroplanes after the Wright Brothers' first flight also had to become increasingly streamlined, to the extent of Concorde and the SR-71 Blackbird, which could not only go fast, but also break the sound barrier many times over.Streamlining was also applied to nautical craft, a.k.a., boats. It's no coincidence that an oil tanker can go nowhere near as fast as a Formula 1 Racing Boat. Why? The racing boat is slipstreamed against the water. However, water is about a thousand times more dense than air, and very much more viscous. The results of these two properties are that streamlining the hull of a boat against water doesn't mean that with the same power you can go as fast as you would do in air.
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