Why is someone who crosses a picket line called a scab? The insult goes back to the 1500s, when “scab” had come to mean a low, mean, rascally person—a scoundrel. Strikes themselves are far older than most people assume. One of the earliest recorded strikes happened in Ancient Egypt in 1152 BC, when artisans of […]
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What is Occam’s razor? Occam’s razor is a principle that says if you have two competing ideas to explain something, you should always prefer the simpler of the two. It is named after William of Ockham, but he never called it “Ockham’s razor” himself. The basic idea behind Occam’s razor is that if you have
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How does a vacuum cleaner create suction? A vacuum cleaner creates suction by making a pressure difference between the air in the vacuum cleaner and the air outside the vacuum cleaner. However, the dirt is not technically being sucked up into the vacuum cleaner but pushed up. There are two kinds of vacuum cleaners currently
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How does electricity get to my house? Electricity gets to my house in three stages. These are generation, transmission, and distribution. The first step is obviously to make the electricity. Most countries use either coal, natural gas, or nuclear power stations. They also use renewables such as solar, wind, and hydro power. These ratios break
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Are there any unpickable locks? There are probably no unpickable physical locks, but some modern high-security locks are very difficult to disable. If given the right tools and enough time, pretty much any physical lock can be picked. And, if picking it is not possible, it can probably be drilled through, or even removed from
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Why do some places use revolving doors? A lot of places use revolving doors because they reduce heating and cooling loss, they keep noise and dirt out, they are easy to open, they are quiet, they don’t need power, and they can regulate the flow of people into a building. The first patent for something
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Why can’t you open an airplane door mid-flight? You can’t open the door while an airplane is flying because of pressure, the design of the door, and because of safety mechanisms. Large planes, such as the 747, have several doors on each side of their fuselage. Each door appears to be closed with only a
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When did cigarettes become mainstream? Cigarettes increased in popularity after their manufacture was automated, but they became mainstream after World War 1. Tobacco wasn’t known in Europe until the Spanish brought it back from South America in the 15th century. Before tobacco arrived, people in Europe had other drugs to smoke, but they were more
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How does slipstreaming work? Slipstreaming works because one vehicle drives closely behind another so that it can ride in the low-pressure wake that follows the first vehicle, reducing the air resistance and reducing the amount of power needed. Unless you are moving in a vacuum, you are going to come up against air resistance. We
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Why is Boxing Day called Boxing Day? Boxing Day is most likely called Boxing Day because of the tradition of wealthy families giving boxes of gifts, money, or leftover food to their servants and tradespeople. However, it could also come from churches giving charitable boxes to people in their congregation. It could be a combination
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