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Compasses
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| A compass is an instrument that is used for navigation (finding directions). It consists of a magnetized arrow which is free to allign itself due to Earth's magnetic field. When you look at a compass, you can see that it shows the capital letters of N, S, E, W which mean North, South, East, and West accordingly. It has been first invented in China in the 11th century. Then it had a main impact in maritime trade due to its power for navigation. A similar compass is invented in Europe in 13th century, and it then originated the liquid compass. Modern navigational compasses use a magnetized needle or a liquid filled capsule (oil, alcohol etc.), and liquid makes the needle to stop more quickly than allowing it to oscillate. Also in many military compasses, there is protractor using a different magnetized needle. There can also be found small compasses in watches, cell phones etc. and they are called solid-state devices which are usually built out of two or three magnetic field sensors, and they provide data for the microprocessor. In this category, you will find compasses with many different features such as digital compasses, compass thermometers, map compasses, liquid-filled compasses, pocket compasses, compass watches, etc. You may choose one of them according to your needs. |
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