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Why do passengers board, alight an aircraft only from the left?

The hold doors are on the right, so with the baggage being loaded/unloaded and re-fuelling taking place, it would be pretty crowded and dangerous. Also on older aircraft, the forward right hand doors were actually designated service doors and emergency exits only. Besides, the left side of the aircraft is where the pilot sits, with the co-pilot in the right-hand …

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Why do particles and anti-particles, when they come in contact, annihilate each other?

For sub-atomic particles like electrons and protons, there exist corresponding particles with the same mass but opposite electrical and magnetic characteristics. For example, the electron’s anti-particle, positron, possesses the same mass as the electron, but carries a positive charge. The anti-particles are produced naturally in radioactive decay. In the universe, the number of regular subatomic particles and anti-particles is not …

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Why do our faces turn red when we do something wrong?

When our faces turn red because of some act that we know to be wrong, it is probably because we are ashamed. Another reason for blushing, as it is called, may well be from anger or shyness. All these emotions disturb the nervous system which controls the flow of blood to the surface of the skin and it is then …

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Neil Gershenfeld

Neil Gershenfeld — Physicist and computer scientist, Gershenfeld heads the Center for Bits and Atoms at the Massachusetts Institute of Technology, where he takes an interdisciplinary approach to quantum computing, nanotechnology, and personal fabrication. Gershenfeld’s research interests are mainly in interdisciplinary studies involving physics and computer science, in such fields as quantum computing, nanotechnology, personal fabrication, and other research areas. …

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Why do oil and water not mix?

Oil and water do not mix because the molecules (tiny particles) of which they are composed are so different. The molecules in oil are much bigger and contain many more atoms than those of water. When different liquids mix, it is because they have similar types of molecules which readily link up with each other, like milk and water. In …

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Neil A. Armstrong

Neil A. Armstrong — The American astronaut Neil Alden Armstrong, b. Wapakoneta, Ohio, Aug. 5, 1930, was the first person to walk on the Moon. Armstrong received his pilot’s license on his 16th birthday. After two years at Purdue University, he joined the navy and flew combat missions over Korea. He returned to Purdue, obtained his aeronautical engineering degree in 1955, …

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Why do objects appear reversed in a mirror?

Objects will appear reversed in a mirror because what you are seeing in a reflection and not a reproduction of the image. If you stand in front of a mirror with your right eyes closed the image in the mirror will appear to show your left eye closed, because the image is facing the opposite direction. In all reflection images …

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Why do not Birds on a wire get a shock?

Now how is that possible? The fact is, for a living creature to get a ‘shock’ there has to be a substantial flow of current through the body. However, there is barely any current running through the bird’s body for two reasons. Firstly, the bird not only forms a circuit with the wire, but it also offers a high resistance …

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Why do newspapers print a combination of four dots – blue, pink, yellow, black – at the bottom of each page?

The four dots – blue (cyan), pink (magenta), yellow and black are registration marks used during printing to help ensure the print is aligned properly. In offset printing technology, which newspapers use, the inked image is transferred from a plate to a rubber blanket, then to the printing surface. These primary colours go into printing a multi-coloured image and have …

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Why do muscles ache after exercise?

Whatever you do, you are using your muscles. Not all of them move at once you have 639 muscles in all but you would be surprised to know how many of your muscles you use doing something as simple as walking. When your muscles are working they produce an acid called lactic acid, which makes the muscles feel tired. When …

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