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Why is there usually a yew in many old churchyards?

Yews have long been associated with religious worship. So it is likely that churches were originally built near the sacred trees rather than the other way round. These trees live longer than any other species in Europe and can grow to an enormous size. Many are thought to be well over 1,000 years old. Yews were revered by the druids …

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Why is the shuttle like a saucer?

You could say because they are both spacecraft. However, the right answer is that they are both made of ceramics. Saucers are made of ceramic material called porcelain, and the space shuttle is covered with ceramic tiles that resist the intense heat of re-entry into the Earth’s atmosphere. Ceramics are materials like pottery. They are made of substances such as …

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Why is the flame of a candle pointed?

The flame of a candle is produced when the wax of the candle melts due to heat and the molten wax rises in the wick. It gets vapourised at its tip, and the vapour starts burning. The chemical reactions that occur are quite complex, giving rise to various colours and different zones of the flame. As the heated gas rises …

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Why is the empty space in a car measured in litres?

Generally, volume in litres is associated with liquid measurements. Space inside a car is a not a perfect cube or an easily calculable shape. Volumes are not always easy to measure for irregular solid objects or spaces. We can use litres and cubic centimetres, or even cubic metres for measuring solid objects, or space that something might fit into, for …

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Why is the Ball-point Pen Called So?

Writing is one of the most important inventions. Humans first used brushes for writing, then thick reeds were used. Feathers were used in medieval Europe for writing. In the mid-19 century, metallic pens and nibs were widely used, while the fountain pen was produced in 1884 by the American, LE Waterman. However, these pens had a lot of problems. The …

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