How do sailing ships sail against the wind? To sail against the wind, sailing ships use a combination of techniques. They angle themselves to increase aerodynamic lift, they use an underwater keel, and they use a zigzag motion called tacking. No one knows when sails were discovered, but the earliest known image of a sail […]
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Is an embassy really foreign soil? No. An embassy is not foreign soil. It is still inside the country where it is located, but it is protected by special rules and immunities. The idea that countries own the land their embassy is on and that it becomes foreign soil is very common, but it is
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Why is it called Area 51? The simple answer is that it was a map designation, but the exact reason why that number was chosen is not completely clear. The site at Groom Lake was near the Atomic Energy Commission’s Nevada Proving Ground, where nuclear testing was carried out. The land there was divided into
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Why does pumice float? Pumice floats because it has a very low density. This is because of all the gas-filled holes inside it. Whether or not something floats depends on how much water it can displace. Objects float in water if they are positively buoyant, which means they can displace more water than their own
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Why are there so many different types of electrical outlets? There are so many different types of electrical outlets because countries built their electrical networks independently, and they all made different choices based on their own technology, traditions, safety rules, and requirements. There are 15 commonly listed styles of electrical plug and outlet around the
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How do you dismantle a skyscraper? There are several ways to dismantle a skyscraper, but none of them are easy. The method depends on where the skyscraper is located, what it is made of, how tall it is, and what is standing around it. The first skyscrapers were built in the 1880s. They were made
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Do people actually live in igloos? People don’t usually live in snow igloos permanently, but some Inuit groups historically used them as winter homes or temporary hunting shelters. The English word “igloo” comes from the Inuit word “iglu,” which means house or home. It does not necessarily mean a house made of snow. In some
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How does a spring work? A spring works by storing mechanical energy when it is deformed and then releasing that energy when it returns to its original shape. Springs don’t have to be metal, but in human-made springs, metal is probably the most common material. There are natural springs as well. The tendons in a
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How do storm drains work? Storm drains work by directing rainwater from roads, sidewalks, roofs, and streets into underground channels, where the water can be controlled and carried away. Before there were cities, storm drains were obviously not necessary. When it rains in nature, the water hits the ground and either soaks into the soil,
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Why are British people called Limeys and Poms? British people are called Limeys because of the citrus juice British sailors drank to prevent scurvy, and they are probably called Poms because of Australian rhyming slang connected to the word immigrant. There are many names for British people around the world. Some of them are affectionate
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