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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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Why do laurel and holy trees have shiny waxy leaves?

Laurel and holy trees have developed special kinds of leaves to seal the water inside themLaurel and holy trees have developed special kinds of leaves to seal the water inside them during the winter months. Both trees are evergreen, inside of dropping all their leaves in autumn; they shed old ones and grow new ones through out the year. In …

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Why do food packages carry Kcal when they actually specify calories and not kilo-calories?

Kilocalories are commonly known as calories and abbreviated as kcal. One calorie (Kcal) has the same energy value as 4.186 kilojoules (kJ), while one kilojoule is equivalent to 0.24 calories. One calorie contains the amount of energy that raises the temperature of one litre of water by 1 degree Celsius.

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