Which is the longest suspension bridge in the world?

The Akashi Kaikyō bridge links the island of Honshu to Awaji island. It has a central span length of 1991 metres, the longest span of any bridge on earth. There are other two spans or sections, each measuring 960 metres or 3,150 feet. The bridge has a total length of 3,911 metres or 12,831 feet. It has six lanes and 23,000 cars pass through it each day. It is also called the Pearl bridge.

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Who discovered the Möbius strip?

The Möbius strip is formed by taking a rectangular strip of paper and connecting its ends after giving it a half twist. It is a surface with only one side and one edge. In 1858, the properties of the strip were discovered independently and almost simultaneously by two German mathematicians August Ferdinand Möbius and Johann Benedict Listing.

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Discovery of wireless transmission

Professor Jagadish Chandra Bose demonstrated that the electric rays had the ability to travel long distances without the help of any wire. He did so by initiating the electric rays using a radiator in the lecture room, which passed through three solid walls of the lecture room, an intervening room, to a third room. The receiver of the radiation used the incoming rays to ring a bell, discharge a pistol, and explode a miniature mine. Bose never patented his findings. Almost about the same time, Guglielmo Marconi devised a system using a transmitter, some coherers and receivers that could send wireless signals through long distances. He was successful in patenting the system and commercializing it.

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Evaporation to precipitation – Time taken by a droplet of water

Water evaporates from oceans, seas, rivers, etc., and rises up in the atmosphere. At the height of several thousand kilometres, these vapours condense to form clouds and eventually droplets. By this time, the droplet may have travelled many miles from its place of origin. Once the droplets reach a certain size, typically 6 mm in diameter, they begin to fall from a great height and would travel thousands of miles.

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Invention of the first vending machine

Hero of Alexandria was a mathematician and an engineer about the time of Christ in the 1st century AD. He built a machine that could dispense holy water by accepting a coin. This was the world’s first vending machine. Its internal structure comprised essentially of levers resembling a balance beam. On one end of the beam, a pan was attached. On the other end of the beam, a plug was attached by a string to a plug that stopped the flow of water. When the coin was dropped inside, the machine, it fell into the pan. The weight of the coin caused the lever to open a valve through which water trickled out. The pan continued to tilt due to the weight of the coin. Finally, the coin fell off and the plug at the other end of the beam shut off the valve, and subsequently the flow of water.

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