Why does an atomic bomb make a mushroom cloud? Because of the speed of the blast and the heat from the fireball. We have all seen images of nuclear bombs being detonated and they always have a very distinctive cloud that is in the shape of a mushroom. These mushroom clouds can be tens of […]
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When were photographs first used in newspapers? The first photograph was published in a newspaper in 1848, but they didn’t become common for a long time after that. Depending on the type of paper, modern newspapers have a lot of photographs. The percentage and the size of the photographs may vary depending on whether the
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Joseph Lister was born in Britian in 1827. He became a doctor in 1950 and a surgeon shortly after. During his career he revolutionized the way surgery was performed, saved countless lives, and made surgery safer for all of us today. He realized that germs were responsible for the majority of deaths after surgery and
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Why is there such a difference between Haiti and the Dominican Republic? There are several reasons. Some of them are the climate, their history, their languages, their population densities, and their governments. Haiti and the Dominican Republic are both on the island of Hispaniola, which is an island between Puerto Rico, Jamaica and Cuba. It
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When did daylight savings time start? It started in Canada in 1908. Daylight savings time is the practice of putting the clocks forward by one hour in the summer and back in the winter. The reason for this is to give people more sunlight throughout the year as the length of the day changes with
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How do some plants move? There are three ways that plants move. Plants can move to face the sun or to move into sunlight. Plants can move when touched or stimulated in some way. And plants can move to find a structure to wrap around. Each type of movement has a different mechanism. Let’s look
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Are any plastics biodegradable? Some are, but most aren’t. It depends on what they are made from and how they are made. Most natural materials biodegrade once they are dead. Inside the cells of the dead material are polymers, which are chains of small molecules strung together. Bacteria and other organisms break down the cell
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What is peat? Peat is a layer of partly decomposed organic matter on the surface of a soil. It has a high water content and a low oxygen content. Accumulations of peat are called peatlands and they are found in 180 countries worldwide, in different quantities. The highest concentrations are in northern Europe, northern
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What is your risk of dying every year? It depends on your gender, age, race, where you live, and so many other factors, but it is possible to make a rough estimate of your chances of dying at every age. A person’s statistical risk of dying at every age is useful knowledge for governments, the
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When we think about important figures in the history of aviation, Orville and Wilbur Wright obviously spring to mind. However, they probably wouldn’t have been able to fly without the work of Otto Lilienthal, a German aviator, who was known as the flying man. Lilienthal wasn’t the first person to build heavier than air flying
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